At least six people were killed on Wednesday when a suicide bomber targeted a bus carrying prison employees outside Pul-e-Charkhi prison in the outskirts of Kabul, reported TOLO News quoting the Ministry of Interior. Three people were reportedly injured in the attack.

The Ministry of Interior revised the toll after Kabul police chief’s spokesperson Basir Mujahid said seven people had died and at least 14 were wounded.

Ministry of Interior spokesperson Najib Danish said three security force members and three civilians, including children, were killed in the attack. Danish said the attacker was on foot and walked towards the bus which was entering the jail premises, AFP reported.

“The attacker walked towards a vehicle that was parked at a gate for security clearance,” Reuters reported an unidentified government official as saying. “He blew himself up before the vehicle could enter the prison premises.”

No group has claimed responsibility for Wednesday’s blast, TOLO News reported. The Pul-e-Charkhi prison houses hundreds of inmates, including Taliban insurgents

This comes just two days after a policeman and a civilian were killed in a suicide explosion bombing outside the offices of Afghanistan’s election body in Kabul. The Islamic State group claimed responsibility for the attack. The attack came after officials at the Independent Election Commission began counting votes cast during parliamentary polls on October 20.

More than 130 people were killed or injured in violence in several parts of Afghanistan during voting for the parliamentary elections.