A Libyan detention center where an airstrike killed more than 50 people two weeks ago is filling up with migrants again, and work has resumed at a nearby weapons workshop.

U.N. and Libyan officials confirmed around 200 migrants have been sent to the center, which was emptied out after the July 3 airstrike. The new arrivals were intercepted at sea by the EU-funded Libyan coast guard, transferred from overcrowded centers or recaptured after escaping in the airstrike.

A migrant who was among those evacuated from the compound and was still in contact with some of those recaptured says a weapons workshop where detainees were forced to work was again operating. The U.N.-backed government in Tripoli blamed the airstrike on Khalifa Hifter's self-styled Libyan National Army.