(CNN) -- A manhunt continues in the Philippines after an armed raid led to a mass prison escape.
As many as 158 inmates fled the North Cotabato District Jail in Kidapawan City in the southern Philippines early Wednesday after armed men attacked the compound, according to Xavier Solda, the spokesman for the Philippines Bureau of Jail Management and Penology (BJMP).
Around 1:15 a.m. local time (12.15 p.m. Tuesday ET) more than 100 armed men attacked the facility, he said. The firefight lasted two hours. One jail officer was killed and another was injured during the conflict.
The inmates escaped through the back portion of the jail as the firefight raged, Solda said. Fourteen men have since been apprehended and six have been killed, he told CNN. Two inmates have voluntarily surrendered. The jail's latest recorded population is 1,511 inmates.
Islamist group suspected
Acting Provincial Jail Warden Supt. Peter John Bongngat Jr. told CNN affiliate CNN Philippines that members of the breakaway Moro Islamic Liberation Front (MILF) group were suspected of being responsible for the attack.
He said some of the escapees were affiliated with the group, which is fighting for an an autonomous region for Muslims in the southern island of Mindanao, home to a sizable Muslim population, in this mainly Catholic country.
"(The escapees) are mostly our Muslim brothers and most of them are (MILF) members," he told CNN Philippines. "But the others likely just went along with the jailbreak."
Bongngat told CNN Philippines that the regional branch of the Philippines National Police (PNP) had provided intelligence that an attack was being planned for New Year's Day.
"We were given intelligence reports (on) December 30," he told CNN Philippines. "We had a conference with the provincial director of the PNP (Philippine National Police) North Cotabato, together with the battalion commander of the Philippine Army," he said.
"And we were prepared because we were expecting that they will attack us on the evening of New Year," Bongngat added. "So all security personnel from the PNP, the BJMP and the Philippine Army were readily prepared for that eventuality."
A clearing operation continues around the jail involving members of the Philippines Special Action Force, the army and the BJMP Special Tactics and Response team, the press release said.
CNN's Sandi Sidhu contributed to this report.
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