Islamabad, Jul 30 (IANS): The Pakistan Army was called in after an unknown number of militants carrying heavy weapons stormed a central jail in Pakistan's Khyber-Pakhtunkhwa province late Monday, Geo News reported.

The Central Jail, located in Dera Ismail Khan city, was housing as many as 5,000 prisoners including 250 inmates belonging to various banned outfits.

Later, proscribed Tehreek-e-Taliban Pakistan (TTP) claimed responsibility for the attack on jail, saying 100 militants, including suicide bombers took part in it.

After the area plunged into darkness as militants destroyed electricity transformers, a curfew was clamped. Deputy Commissioner Mushtaq Jadoon said it had been imposed to avoid any damage to public.

He claimed that militants were still holed up in Twon Committee locality near the detention facility. But he was not immediately sure if any prisoner had fled or how many armed men launched the attack.

The officer, however, said that six suspects were arrested while two policemen with minor injuries were taken to a nearby hospital for treatment.

Independent sources claimed that at least 40 prisoners were freed in the attack. It appeared to be the largest jail break after Bannu mass jail breakout in which hundreds of militants including a key Taliban figure involved in a life attempt on former president Pervez Musharraf were freed. However, officials didn’t confirm the report.

Sources said gun shots and explosions were also heard inside the prison. They said that the militants targeted police vehicles with hand grenades.