ISIS claimed responsibility Monday for an attack on a prison in eastern Afghanistan. At least 21 people died and 43 were injured when a suicide bomber drove a truck into the Jalalabad facility's entrance.
Police believe several militants slipped away into a nearby residential complex, making it more difficult to flush them out.
The prison holds about 1,500 inmates. Several hundred are believed to be members of ISIS. Security forces recaptured around a thousand inmates who had escaped during the attack.
This comes a day after authorities said Afghan special forces killed a senior ISIS commander near Jalalabad.
A spokesperson for the governor of Nangarhar province said Monday morning that three attackers had been killed, but sporadic gunfire continued from the prison grounds and nearby residential area.