The last American troops flew out of Afghanistan on Monday, with the country again under the control of the Taliban, a fundamentalist group that ruled the nation for five years before U.S.-led forces ousted them in 2001. Clashes between Taliban fighters and rival militias continued Wednesday in some pockets of the country as the new rulers tried to consolidate their hold.

Refugees fleeing the Taliban’s ultraconservative brand of Islam had swelled the population of Kabul, and the airport was besieged by Afghans desperate to find a way out before the last U.S. planes left.

President Biden had set a deadline for U.S. troops to leave Afghanistan by Aug. 31. However, efforts to evacuate U.S. citizens and Afghans who worked with Western governments and agencies were rocked by a suicide bomb attack at the airport that killed nearly 200 Afghans, according to a senior health official, and 13 U.S. service members.

Washington blamed an Islamic State affiliate for the attack, and on Saturday the U.S. said it conducted an airstrike against the group in Afghanistan’s eastern Nangarhar province, likely killing two militants, including a leader responsible for planning the attack. 

On Sunday, a U.S. drone struck a vehicle in a residential area of Kabul, preventing what the Pentagon said was an imminent attack on the airport. An official said the vehicle was carrying suicide bombers affiliated with Islamic State. Family members and a neighbor said the strike killed 10 civilians—all relatives of a former interpreter who had been seeking a U.S. special immigrant visa because he feared retribution from the Taliban. The Pentagon has pledged a transparent investigation.