Zamboanga City, Philippines - Four marines were killed Saturday when suspected Islamic militants attacked their encampment on a southern Philippine island, a regional military spokesman said.

Ten more marines were wounded in the fighting that erupted when suspected Abu Sayyaf rebels fired mortars at the marines encampment in Patikul town on Jolo island, 
1,000 kilometres south of Manila, Major Eugene Batara said.

Batara said no casualties were reported on the enemy side.

The attack occurred as military troops intensified operations against two renegade Moro Islamic Liberation Front (MILF) commanders in the provinces of Maguindanao and Lanao del Norte on the strife-torn nearby island of Mindanao.

The two MILF commanders have been blamed for leading attacks on towns and villages that left dozens of civilians dead and displaced more than 360,000.

The hostilities flared up after the Supreme Court this month stopped the government and MILF peace negotiators from signing an agreement that would have expanded a Muslim autonomous region in Mindanao.

The Philippine government eventually scrapped the deal amid strong opposition by Catholic politicians, but the MILF insisted that the government should honour the agreement, which was negotiated for more than four years.

The MILF is fighting for an Islamic state on Mindanao while the Abu Sayyaf is the smallest but most violent Muslim rebel groups in the southern Philippines. The al-Qaeda-linked group has been blamed for deadly terrorist attacks in the country. (dpa)