A school classroom that will be used as a polling center for the coming general elections in northern Philippines was burned down by unknown arsonists early Saturday, the military said.

Major Harold M Cabunoc, a spokesperson of Philippine Army's 9th infantry division, said in a statement that one classroom of the Sipocot South Central School in Sipocot town in Camarines Sur province was set on fire at around 12:30 a.m., coincided with a power interruption.

Blesilda Delos Llagas, a school teacher of the town, said that the burned classroom was located about 100 meters behind the school principal's office which contained some Precinct Count Optical Scan (PCOS) machines intended for the 2010 General Elections on May 10.

Delos Llagas believed that the PCOS machines were not the target of the arsonists. She said that there had been similar incidents of forced-entry and burglary in the same school for the past years.

Lt.Col Luis Rex Bergante, Commander of the 31st Infantry Battalion based in Sipocot town, immediately dispatched soldiers to investigate the incident, the military said in the statement.

The soldiers promptly conducted pursuit operations and thorough investigation together with the personnel from Bureau of Fire Protection, the statement said.

Colonel Cirilo Teodoro Torralba, Commander of the 902nd Brigade which has jurisdiction over Camarines Sur, immediately directed the 31st Infantry Battalion to conduct further investigation.

He also ordered his troops to conduct security patrols in the vicinity of all other schools which are used as polling centers to prevent similar incidents from happening.