Around 15 to 20 prisoners broke loose after attacking the jail officials at a prison in Khyber Pakhtunkhwa's Chaman area on Thursday.
Police said that the incident occurred as the prisoners attacked the officials while exiting their barracks for Eid ul Adha prayers.
The prisoners snatched a weapon from a jail official and escaped, they added.
The barrack incharge said that the escaped prisoners are accused of offences under Section 302 (punishment of qatl-i-amd) and other serious crimes.
Meanwhile, the jail authorities said that the prisoners had opened fire with the same Kalashnikov they had snatched from the officer standing outside the main gate of the facility.
Pakistanis are celebrating Eid ul Adha, aka 'Bakra Eid' today, which marks the end of Hajj pilgrimage offered in the last month of Islamic calender.