Davao City, Philippines  - Seven suspected Muslim separatist rebels were killed in a clash with police officers in the southern Philippines, police said Wednesday.

The clash occurred in the village of Napnapan in Pnatukan town, Compostela Valley province, 930 kilometres south of Manila, on Tuesday.

Senior Superintendent Francisco Villaroman, a regional police intelligence chief, said the rebels were suspected to be members of a breakaway group of the Moro Islamic Liberation Front (MILF).

He added that the rebels were "engaged in extortion activities."

"These are lawless elements and had been subjects of a complaint by the governor, businessmen and people they have been threatening," Villaramon said.

Villaroman said police officer seized three rocket-propelled grenade launchers, three rocket grenades, garand rifles and hand grenades at the site of the firefight.

The MILF is the largest Muslim rebel group fighting for a separate Islamic state in the southern region of Mindanao. It has been waging the secessionist struggle since 1978.

The rebel group has been holding peace talks with the Philippine government, but the negotiations have been suspended due to renewed fighting in Mindanao.

Some MILF members frustrated with protracted peace talks with the Philippine government have resorted to criminal activities to protest the negotiations and raise funds. (dpa)