Taliban has claimed the responsibility for the attack. Journalists received calls by Taliban militants who said they have targeted the prison directorate in the north of the city.
"There are lots of dead," a police official said on condition of anonymity. Another police official , also on condition of anonymity said: "At least eight people must have been killed."
A civilian witness said that he saw two sucide attackers. "One opened fire at the main gate guard and police fired back.
Then all of a sudden, he donated. The second one had already made his way to the front entrance and then he detonated," the civilian said.
More details are awaited.
OneIndia News (With inputs from Agencies)