Gunmen were holding about 57 people hostage Thursday after abducting them from a village in a remote part of the southern Philippines.

The hostage-takers, who are believed to be government-armed militiamen, took about 75 people from the hamlet of San Martin in Agusan del Sur province and the local village school. They later released all 17 of the student hostages and an elderly woman after negotiations with local officials.

"We have them already," said senior police superintendent Nestor Fajura. "No more children [hostages]."

Police chief superintendent Jaime Milla said the gunmen were dismissed militiamen who have turned to banditry and extortion. He said they have been targeting mining and logging companies.

Police were reported to be pursuing the gunmen following a failed Wednesday attempt to serve arrest warrants in a nearby village for two brothers sought in connection with the killing of four rival clan members. The gunmen opened fire as police approached the village, Fajura said.

Last month, gunmen killed 57 people in an election convoy in another southern province, which has been placed under martial law.

The southern Philippines is plagued with violence due to bandits, government-armed militias, and communist and Muslim insurgents.

With files from The Associated Press