FBI Director James Comey says the agency arrested more than 10 people, radicalized through social media, plotting to kill Americans on Independence Day.
It is the first such release in five months from the U.S. prison at Guantanamo Bay, Cuba, and the first to be approved by Defense Secretary Ash Carter.
The White House said Tuesday that President Obama would remove Cuba from the U.S. list of state sponsors of terrorism. Iran, Sudan and Syria are also on it. But some states have made it off, too.
President Obama has launched a sustained, long-term military campaign against the Islamic State, also known as ISIS or ISIL. Four legal experts debate whether he had the constitutional power to do so.
The Islamist militants had taken hostages at a university campus in Garissa. In 2013, militants from the same group carried out a similar operation on the Westgate Mall in Nairobi, the capital.
U.S. defense and intelligence officials tell NPR that the list appears to have been derived from publicly available sources and not a breach of a government server.
Tunisia's prime minister says at least 21 people — including 17 foreign tourists and two gunmen — died in the attack at the National Bardo Museum, a popular tourist attraction in the capital.