(CNN) -- Pakistani police raided a school occupied by militants Saturday, killing four people, authorities said.
The attack occurred at a school in Swabi city in Khyber Pakhtunkhwa province, according to senior police official Haji Khan.
Fifty militants were rounded up following the gunfire, which lasted more than four hours, he said.
A massive amount of arms and ammunition were recovered from the school.
Swabi is the hometown of Sheikh Khalid Haqqani, the deputy chief of the Tehreek-e-Taliban Pakistan.
Pakistani Prime Minister Nawaz Sharif reiterated in parliament this week that he still wants to hold talks with militants instead of resorting to a military operation.
A four-member committee has been appointed to push forward with negotiations.