LEGAZPI CITY, Philippines-?Government troops launched rescue operations for a policeman believed abducted by communist rebels following an ambush in Sorsogon that killed four other policemen and one of the rebels, authorities said Tuesday.

Four policemen were killed when their vehicle hit a mine planted by the rebels in Bulan, Sorsogon, in an ambush that also left one rebel dead, police said.

Four other police officers were wounded in the attack by members of the communist New People?s Army (NPA).

Soldiers who rushed to the scene of the blast engaged rebels in a gun battle that left one of the rebels dead, police added.

Senior Supt. Hereberto Olitolquit, provincial police chief, said the attack may have been intended to avenge the killing of 10 NPA fighters by government troops in the same region in September.

Capt. Razaleigh Bansawan, spokesperson of the Army?s 901st Infantry Brigade, said PO1 George Jordan was missing after the clash that killed four of the policemen.

Bansawan identified those killed as Insp. Jefferson de Leon, SPO1 Johnson Gerola, PO2 Darwin Detoito, PO1 Ryan Padriqui?all members of the 509 Police Provincial Mobile Group based in Sorsogon City.

Bansawan identified the three wounded policemen as PO1 Frans Guamos, PO1 Alain Lanuza and PO1 Alwin Baldano.

Maj. Harold Cabunoc, information officer of the Army?s 9th Infantry Division, said the eight policemen, on board their patrol car, were on their way to Barangay J. P. Laurel to respond to a report that the home of a certain Gerry Goyala was ransacked by about 15 suspected rebels at around 11:45 a.m.

While on their way to Goyala?s home, a land mine exploded at a road section in Barangay Antipolo, hitting the police car, he said.

Cabunoc said the impact of the explosion was so strong that it immediately killed two policemen and created more than a meter-wide crater.

A gunfight followed, lasting for about 30 minutes.

Government troops recovered from the ambush scene unused Molotov cocktails, an unused land mine and four M-16 rifles after the guerrillas fled the area.

An unidentified communist rebel was killed in the attack, said Senior Supt. Olitoquit, Sorsogon police provincial director, in a report to the Bicol regional police headquarters in Camp Simeon Ola in Legazpi City.

On Monday, the Sorsogon-based Celso Minguez Command admitted to the killing of the policemen. Rey M. Nasol and Jonas Cabiles Soltes, Inquirer Southern Luzon