Philippines ? Maoist guerrillas used bombs to destroy equipment Sunday at an international airport that is under construction in the central Philippines.

About 30 members of the New People’s Army rebels did not harm any workers in the attack on the sprawling site at Silay City in Negros Occidental province, but the assault could delay completion of the Japanese-funded project by about two months, police said.

The communist guerrillas, disguised as policemen and armed with assault rifles, barged into the construction site shortly after midnight and disarmed the guards. They destroyed a computerized cement-making facility and a standby power generator using homemade bombs and kerosene, Silay police chief Supt. Celestino Guara told The Associated Press by telephone as he inspected damage at the airport.

The guerrillas fled after seizing 18 pistols, three shotguns and seven two-way radio sets from guards. The attack damaged equipment worth $500,000, Guara said, citing people involved in the project.