At least 21 people have been killed in ongoing fighting between Afghan security forces and gunmen who raided a jail overnight in an attack claimed by ISIS group, officials said on Monday.
Among the dead were prisoners as well as civilians, prison guards and Afghan security personnel, Attaullah Khogyani, a spokesman for the governor of Nangarhar province, told Al Jazeera.
Another 43 people have been wounded in the attack in the provincial capital Jalalabad that began late on Sunday when an ISIS suicide bomber slammed his explosive-laden vehicle into the gate of the prison.
Afghan officials said the death toll could rise.
Police were forced to divert manpower to recapture escaped prisoners and by noon on Monday around 1,000 had been caught, according to Khogyani.
The prison houses about 2,000 inmates, including many from the ISIS and the Taliban.
Earlier, a Taliban spokesperson said on Twitter that the group was not involved in the attack, which came on the final day of a rare truce between the armed group and the Afghan government to mark the Eid al-Adha Muslim holiday.
The prison attack came a day after the Afghan intelligence agency said a senior ISIS commander was killed by Afghan special forces near Jalalabad, about 150km (93 miles) east of the capital, Kabul.
Nangarhar province has been hit by regular attacks, several of them claimed by ISIS.