Fourteen troops were killed and seven others injured Saturday in an ambush of Yemen's headquarters of the intelligence service in Tawahi, Aden, the defense ministry and three local security officials said.
The word "terrorism" in the United States usually brings to mind plots linked in some way to al Qaeda, while the danger posed to the public by white supremacists, anti-abortion extremists and other right-wing militants is often overlooked.
CNN's Erin Burnett discusses the arrests of three al Qaeda suspects in Spain.
Al Qaeda's Yemeni affiliate is trying to attack the U.S. by recruiting Westerners, CNN's Barbara Starr reports.
CNN's Erin Burnett discusses new concerns over the the threat of al Qaeda in the northern region of Mali.
Islamic radicals linked to al Qaeda have seized the northern half of Mali, one of Africa's largest nations, and there are widespread concerns that the region could soon become a terrorist haven.
CNN's Erin Burnett reports from Mali on why the northern region of Africa is important.
There is no credible information that terrorists are plotting an attack to coincide with the Fourth of July holiday, federal law enforcement officials said.
Land mine explosions have killed at least 73 people in Yemen's Abyan province since al Qaeda fighters were defeated two weeks ago, the Yemeni Defense Ministry said. Among those killed were 23 soldiers.
Pakistani security forces arrested a key al Qaeda leader near the nation's border with Iran, military officials said Wednesday.
Two New York men pleaded guilty in federal court Monday to providing material support to al Qaeda, according to a statement from Manhattan U.S. Attorney Preet Bharara.
Azzan, the last al Qaeda in the Arabian Peninsula (AQAP) stronghold in south Yemen, is to be handed over to government authorities within days, two Yemeni senior security officials in Shabwa province told CNN on Saturday.
Yemeni troops raided a third al Qaeda stronghold in a southern province, killing 40 suspected militants, authorities said Friday.
Yemen's army has retaken most of Jaar, the final al Qaeda stronghold in the country's southern Abyan province, forcing hundreds of militants to flee the town, two local security officials told CNN.
CNN's Barbara Starr reports on the U.S. drone strike that killed al Qaeda's number 2 leader, Abu Yahya al-Libi.
The news that Abu Yahya al-Libi, the No.2 leader of al Qaeda, is now confirmed to have been killed in a CIA drone strike in Pakistan's tribal region along the border with Afghanistan further underlines that the terrorist group that launched the 9/11 attacks is now more or less out of business.
A senior al Qaeda leader and another member of the terrorist network were killed in a security operation by Afghan and coalition forces, NATO said Tuesday.
Thirty-eight al Qaeda militants were killed in clashes with Yemen's military, local security officials said Friday.
An al Qaeda video calling for "electronic jihad" illustrates the urgent need for cybersecurity standards for the most critical networks in the United States, a group of senators said.
The Yemeni government blamed an affiliate of al Qaeda in the Arabian Peninsula on Tuesday for a massive suicide bombing that killed more than 100 soldiers a day earlier.
A suicide bomber dressed in a military uniform set off a blast that killed more than 100 soldiers Monday, authorities said, in what appears to be the deadliest attack ever on troops in Yemen.
Fierce clashes between government troops and al Qaeda fighters Sunday morning in Yemen left 21 people dead, two local security officials told CNN.
CNN's Brian Todd reports on Saudi Arabia's efforts to penetrate al Qaeda's most dangerous branch.
Al-Qaeda's leader is calling for the Yemeni people to rise up against the country's new president, portraying him as the stooge of the unpopular former president, Ali Abdullah Saleh, and the United States.
Government troops in southern Yemen on Sunday attacked al Qaeda hideouts, killing two dozen suspected militants in the latest push to clear the area of the terror organization, local security officials said.
A former double agent who risked his life to spy for the U.S. explains how he became trusted.
The infiltration of a Middle Eastern terror network by a mole who helped foil a plot to blow up a U.S.-bound plane was a "phenomenal," "brilliant" and "powerful" success, experts said Wednesday.
A man who volunteered as a suicide bomber for a terrorist group intent on blowing up a U.S.-bound plane was working instead as an intelligence agent for Saudi Arabia, The New York Times reported Tuesday, citing American and foreign officials.
The U.S. says it's foiled a plan by al Qaeda to blow up a U.S. bound flight. CNN's NIc Robertson explains.
Three months before he was killed by a U.S. drone strike, Fahd al Quso, one of al Qaeda's top operatives in Yemen, spoke at length to a local journalist. He was asked why al Qaeda in the Arabian Peninsula had stopped plotting against the United States. Was it because all efforts were devoted to an internal project?
U.S. and other intelligence agencies recently broke up a plot to bomb an airliner and have seized an explosive device that is similar to ones previously used by al Qaeda, officials said Monday.
A day after an airstrike killed a senior al Qaeda operative in southern Yemen, militants attacked two government military posts in the region, killing 26 soldiers and taking 16 hostage, officials said.
In his first public speech since being inaugurated as president of Yemen, Abdu Rabu Mansour Hadi promised a strong fight against al Qaeda and political reconciliation at home.
A U.S. drone hit an al Qaeda training site in southern Yemen, killing 13 suspected militants, three security officials said.
One year after the killing of Osama bin Laden in Pakistan, CNN's Reza Sayah investigates al Qadea in Pakistan.
Most Muslims in several key Middle Eastern and Asian countries hold negative views of the terrorist network al Qaeda a year after U.S. forces killed its leader, Osama bin Laden, according to a recent survey.
On May 16 last year, a 22-year-old Austrian named Maqsood Lodin was being questioned by police in Berlin. He had recently returned from Pakistan via Budapest, Hungary, and then traveled overland to Germany. His interrogators were surprised to find that hidden in his underpants were a digital storage device and memory cards.
CNN's Brian Todd reports on a newly-exposed 2008 al Qaeda plot to bomb the Long Island Railroad.
An internal al Qaeda document reveals new details in the 2006 plot to bring down planes using liquid explosives, including the level of al Qaeda's technical expertise.
Nearly a year after commandos killed Osama bin Laden at a compound northern Pakistan, U.S. officials "still have work to do" in order to defeat al Qaeda, a top counterterrorism official said Sunday.
The fourth-most wanted al Qaeda leader in Yemen was killed Tuesday in an airstrike in the northeastern province of Mareb, the Yemeni government announced.
Five troops and eight militants were killed in Yemen's business capital of Aden when suspected al Qaeda militants attacked a security checkpoint Saturday, three security officials told CNN.
Twenty-eight suspected members of al-Qaeda were killed Friday in the city of Lord, in Yemen's Abyan province, in military operations, state media reported.
At least eight soldiers died and five others were injured when suspected Islamist militants attacked a military post in Yemen's eastern Mareb province early Tuesday, three security officials and a Defense Ministry official told CNN.
Al Qaeda militants seized control of a military base and two checkpoints during raids in southern Yemen on Monday in which at least 30 people died, security officials and residents said.
Yemen has poured thousands of troops into a battle with al Qaeda fighters in two southern provinces amid new airstrikes that killed a dozen of the militants Thursday, security officials said.
Suspected U.S. drones targeted militant hideouts in southern Yemen, killing six people and injuring five others, security officials said Saturday.
Al Qaeda leader Ayman al-Zawahiri calls on Afghans to rise up against Western troops -- especially American forces -- in their country and back the Taliban, according to a recent audio message posted on jihadist web forums Wednesday.
"Lone wolves" who plot to carry out small-scale attacks on soft targets, like those in which seven people have been killed in France, could be the future of terrorism, a security expert has warned.
Gunmen fatally shot an American teacher in the Yemeni province of Taiz on Sunday, two defense ministry officials said.
Four soldiers in Yemen were killed and seven others injured Tuesday morning when a suicide bomber attacked a checkpoint in the province of al-Baitha, two security officials said.
Al Qaeda in the Arabian Peninsula is threatening to kill the 73 Yemeni troops it is holding hostage if the government does not release al Qaeda prisoners.
CNN investigates the al Qaeda printer bomb plot and the potential damage the bomb could have caused.
Al Qaeda announced the death of a regional commander in Yemen, whom the group described as one of "its sheikhs of jihad and support," according to an online terror monitoring group.
The death toll from a sophisticated attack by Islamic extremists against soldiers in Yemen jumped to 184 Tuesday, three Yemeni officials told CNN.
Suicide bombers targeted a Yemeni military camp southeast of the capital Saturday, killing a soldier and a civilian and wounding eight others, a top Republican Guard official said.
Al Qaeda in the Arabian Peninsula announced its responsibility for the presidential palace attack last Saturday in Yemen's southern province of Hadramout.
Peter Bergen, national security analyst, explains Saif al-Adel's background and how he was reportedly arrested in Egypt.
Investigators in Egypt said a man they seized Wednesday is a wanted for terror-related crimes, but he is not Saif al-Adel, a notorious leader in the al Qaeda terror network.
The Obama administration on Tuesday evening issued rules that allow the president to limit the instances in which foreign citizens suspected of links to al Qaeda must be handed over to the military for trial.
The call came into the London Metropolitan Police bomb squad in the early hours of the morning. Isolated at the East Midlands airport in central England was a UPS package dispatched from Yemen, containing a laser printer that Saudi intelligence believed had been converted into a bomb.
The man who smuggled a bomb in his underwear aboard a commercial airliner on Christmas Day in 2009 has been sentenced to life in prison, months after he pleaded guilty for his role in what officials later determined was an al Qaeda plot.
Death sentences were carried out Sunday by al Qaeda members against three people after al Qaeda-run courts convicted them of spying for the Yemeni government, the United States and Saudi Arabia, according to numerous sources and eyewitnesses.
Somalia's Al-Shabaab rebel movement has tightened its ties to the al Qaeda terror network, with its leader pledging loyalty to al Qaeda leader Ayman al-Zawahiri.
Yemen'shighest military authority Sunday announced its willingness to open channels of dialogue with al Qaeda in hopes of reaching a long-term cease-fire agreement.
Three suspected air strikes hit militant targets in southern Yemen Monday night and Tuesday morning, killing at least nine people believed to be linked to al Qaeda, Yemeni security officials said.
The al Qaeda terror network is weakening and the embattled Afghan government is making modest strides, but cyber security threats are on the rise and Iranian nuclear aspirations remain a major peril.
Al Qaeda's leadership has sent experienced jihadists to Libya in an effort to build a fighting force there, according to a Libyan source briefed by Western counter-terrorism officials.
Six al Qaeda in the Arabian Peninsula operatives -- including one high-value target -- were captured by Yemeni security forces, the country's embassy in the United States said Tuesday.
Al Qaeda leader Ayman al-Zawahiri has claimed responsibility for the capture in August of a 70-year-old U.S. citizen in Pakistan, according to a number of radical websites known for carrying militants' messages.
At least 11 suspected al Qaeda militants were killed in Yemen's southern province of Abyan in clashes that erupted Tuesday night and continued for at least 14 hours, according to officials and local residents.
A half-hour video featuring the leader of al Qaeda, Ayman al-Zawahiri, was posted Tuesday on a radical Islamist website.
CNN's Nic Robertson reports on the killing of a radical cleric who inspired al Qaeda followers by preaching in English.
Earlier this week, al Qaeda issued the seventh issue of Inspire, a glossy English-language online magazine that emerged as a mouthpiece for the preaching of now-dead American-Yemeni terrorist cleric Anwar al-Awlaki.
Ten years after the devastating attacks on America, Defense Secretary Leon Panetta recently said the United States is "within reach of strategically defeating al-Qaeda."
Born and educated in the United States, how did Anwar al-Awlaki, a charismatic Muslim cleric, go from "all-American boy" to a terrorist spokesman and recruiter for al Qaeda in the Arabian Peninsula?
The U.S. confirms American-born Muslim cleric Anwar al-Awlaki is dead. CNN's Mohammed Jamjoom reports.
A deadly bombing in Abuja has launched a little-known Islamic extremist group onto the terrorism radar, raising U.S. officials' concern about the spread of the influence of al Qaeda.
A Cuban man arrested in Spain this week for alleged ties to al Qaeda was released Friday on provisional liberty, but must report daily to police, a National Court spokeswoman told CNN.
Spanish Civil Guards have arrested a Cuban man on the Mediterranean island of Mallorca on suspicion of belonging to Al Qaeda, the Interior Ministry said in a statement Tuesday.
The U.S. Embassy in Algeria has received "threat information," the State Department said Friday, noting that al Qaeda and its affiliates continue to pose a "significant terrorist threat."
U.S. officials reported the death of an al Qaeda figure identified as the terrorist network's chief of operations in Pakistan, the latest in what they called a series of significant blows to the terrorist network.
Al Qaeda leader Ayman al-Zawahiri has apparently released a new message to coincide with the 10th anniversary of the 9/11 terror attacks, in which he praises the Arab Spring as a "devastating blow" to the United States.
Al Qaeda is weakened but remains a significant threat to the United States, the nation's top intelligence officials told a congressional committee Tuesday.
Lyzbeth Glick Best recalls her final conversation with her husband, who helped overtake the 9/11 hijackers on Flight 93.
U.S. intelligence officials have warned that al Qaeda may be planning an attack targeting either New York City or Washington around the time of 10th anniversary of 9/11.
The Pakistani intelligence service has arrested a senior al Qaeda leader who sought to attack targets in the United States, Europe and Australia, the Pakistani military said Monday.
Newly-released video shows smoke rising minutes after United Airlines Flight 93 crashed in Pennsylvania on 9/11.
Clashes between al Qaeda fighters and government troops since May in southern Yemen have killed 300 militants, the country's Interior Ministry said Thursday.
The death of al Qaeda's No. 2, Atiyah Abdul Rahman in Pakistan, is a hammer blow to the terrorist organization.
Al Qaeda's second-in-command, Atiya Abdul Rahman, has been killed in Pakistan, a U.S. official said Saturday.
Seven government troops were killed and six others injured on Friday in fierce clashes with suspected al Qaeda militants in Yemen's southern Abyan province.
At least 29 people have been killed and 62 injured from both sides in Yemen's Abyan province as clashes entered a new phase, a senior security source in Abyan said Wednesday.
Eight government troops were killed and at least 28 soldiers were injured in Abyan province when suspected al Qaeda militants attacked the governmental military base for Brigade 211 in Dofas district, a security official in the district confirmed.
Residents of a town in southern Yemen say it has been seized by Islamists connected to al Qaeda.
Egyptian military and intelligence officials say they are preparing to launch an operation against al Qaeda cells that have recently been established in the restive Sinai peninsula.
CNN's Reza Sayah responds to a Washington Post report that government agencies believe al Qaeda is no longer a threat.
The new head of al Qaeda describes Syria's president as "the leader of criminal gangs, the protector of traitors," and applauds anti-government protesters seeking to topple him, in a video that appeared on extremist websites this week.
An Al Qaeda leader who was on the Yemeni government's wanted list was killed in clashes with the army, the country's defense ministry said Wednesday.
Militants gunned down 10 soldiers at a military checkpoint in southwestern Yemen, authorities said Thursday.