Fernando Batul was driving to his radio station in Puerto Princesa city, 580 kilometers (360 miles) southwest of Manila, when two men on a motorcycle fatally shot him four times, Mayor Edward Hagedorn and radio reports said.

A commentator for local Radio DYPR, Batul had criticized the city government over the contracts of Filipino workers it deployed to Taiwan and had earned officials' ire for interviewing local communist guerrillas, the Philippine-based Center for Media Freedom and Responsibility said.

Last month, two unexploded hand grenades were found in front of Batul's home, with a note warning his family would be harmed if he continued with his critical commentaries, the center said. Police safely detonated the grenades and no one was hurt.

Hagedorn _ who told Manila Radio DZMM that Batul was his strident critic whom he sued for libel _ offered a 500,000 peso (US$9,600; euro7,519.39) reward for the capture of the killers and ordered police to solve the case in 48 hours.

Batul was the former vice mayor of the city, but was unseated when the current vice mayor won an electoral protest, Hagedorn said.

Before Batul's slaying, the National Union of Journalists of the Philippines had listed 78 reporters killed since democracy was restored in the country in 1986.

Last week, the Brussels-based International Federation of Journalists renewed its concern about the safety of journalists in the Philippines, saying the situation "has gone from bad to worse" after a Filipino journalist was beaten by a local official that week, just hours after a tabloid photographer was murdered.