"U.S. citizens are strongly encouraged to maintain a high level of vigilance," the agency said on its website.
The FBI said Ayman al-Zawahri and Osama bin Laden coordinated the 9/11 attacks.
Mohammad Ahmad al-Qahtani was flown back to Saudi Arabia, to a treatment facility.
Boston Marathon bomber Dzhokhar Tsarnaev's $1,400 COVID-19 stimulus payment can be used to help pay the millions of dollars he is ordered to pay his victims, a judge has ruled.
Saturday's attack marked the first known time that a suicide bomber has killed victims in eastern Congo, where an Islamic State group affiliate earlier this year took responsibility for a suicide bombing near another bar in Beni who had caused no other casualties.
Jeffrey Rambo, an agent who acknowledged running checks on journalists in 2017, told federal investigators the practice is routine.
U.K. police say an explosion in a taxi outside a Liverpool hospital that killed the suspected bombmaker is being treated as a terrorist incident.
The Paris Terror Attacks of 2015 live in the minds of the French every day, but especially on Nov. 13. Here’s a look back at what happened the night of the attacks.
While DHS said it had no credible information on a specific threat, the agency warns in its latest national terrorism advisory bulletin that mass gatherings for the upcoming religious holidays could be potential targets.
A senior al-Qaida leader was killed Friday in a U.S. airstrike, officials said.
ISIS says its members are responsible for a deadly suicide bombing on a Shiite mosque in southern Afghanistan.
The Supreme Court sounds ready to reinstate the death penalty for convicted Boston Marathon bomber Dzhokhar Tsarnaev.
The Taliban have ruled out cooperation with the U.S. to contain extremist groups in Afghanistan.
The nation is just one day away from marking the 20th anniversary of the Sept. 11 terror attacks and stories of bravery from those who responded are still being told.
Dan Berschinski was just 17 on the morning that the World Trade Center was attacked by terrorists. Now at 37, the retired Army infantry officer is reflecting on that tragic day and the role he and other young soldiers played in Afghanistan.
This class of Florida second graders had a front-row seat as the horror of September 11th unfolded. While all have taken different paths, each one was forged by history from the moment they never expected.
The chief of staff to President George W. Bush remembers the start of that Tuesday September morning like everyone: Blue skies and the sun shining. But he was not in New York or Washington; he was with the president at a Sarasota elementary school.
Cutting-edge DNA technology will be used to analyze the remains of more than 1,100 victims of the Sept. 11 attack on the World Trade Center that have yet to be identified.
The U.S. continued with evacuations in Kabul on Friday with tighter security measures amid warnings of more possible attacks.
The president authorized $500 million on Monday in aid relief to assist Afghan refugees amid chaos as the Taliban take over the country.