The reward system was announced after President Gloria Macapagal Arroyo gave the police and the justice department a 10-week deadline to identify those responsible for the extra-judicial killings in the country.

Director General Oscar Calderon, national police chief, said the reward system would hopefully address ''the seeming apathy and reluctance of some witnesses to share information.''

Under the system, the police would pay between P50,000 and P100,000 ($ 1,000 and $ 2,000) for confidential information that could help police establish cases against suspects.

''Our aim is to enlist the cooperation and support of all concerned sectors to complement all ongoing police action on cases of slain journalists and militants,'' Calderon said.

On Tuesday, Arroyo ordered law enforcement authorities to ''jail suspects in at least 10 media or leftist killings'' within 10 weeks.

She issued the directive after three leftist activists and a photojournalist were killed in separate attacks within 24 hours.

Arroyo earlier urged witnesses in the killings to come forward to help authorities hunt down perpetrators.

But human rights groups noted that many witnesses to the killings are too frightened to come forward and the government must first strengthen its witness protection laws.

Leftist activists have blamed the Arroyo administration for the killings, saying the murders were part of the government's campaign aimed at ending the 27-year-old communist insurgency

They also warned that killings and abductions of activists have intensified after Arroyo hailed a military general suspected to be involved in extra-judicial killings last week.

Since Arroyo became president in 2001, at least 305 leftist activists and 46 journalists have been killed in the Philippines, according to a human rights watchdog and a media group.