Turkish authorities believe the Istanbul bombing points to ISIS and a cell of Russian speakers, a contingent that makes up a large portion of the terrorist group.
It exploded early Sunday on a busy street in the Karada neighborhood, where people were gathering to shop and socialize during a lively Ramadan night. People had just finished watching a soccer match.
A senior Turkish official identified the attackers' nationalities, according to the Dogan News Agency. Police have carried out raids looking for suspects in the attack that killed more than 40 people.
NPR's Kelly McEvers interviews Brett McGurk, special presidential envoy for the Global Coalition to Counter ISIL, about the fight against ISIS in the wake of the Istanbul airport attack.
More than 230 people were injured on Tuesday in an attack by three suicide bombers, Turkish authorities say. Less than a day later, flights have resumed at Europe's third-busiest airport.
Turkey is currently battling Syrian President Bashar Assad, the Islamic State and Kurdish separatists in southeast Turkey. All the battles are draining the country, and none is going well.
Iraqi forces say they have wrested control of Fallujah from Islamic State militants after nearly 5 weeks of intense fighting. The militant group has controlled the city for the past 2 ½ years.
Part of the U.S.-led coalition against the Islamic State in Iraq and Syria is seaborne. The Navy's USS Truman has been in the Persian Gulf but now is in the Mediterranean, on its way home to Virginia.
The gunman in Sunday's attack at a gay nightclub used Facebook to search for and post terrorism-related content before and even during the assault, according to Wisconsin Sen. Ron Johnson.