The Philippines and Indonesia have signed an agreement resolving a sea border dispute after 20 years of negotiations, with the neighbors' leaders vowing to forge closer ties.

Philippine President Benigno Aquino III and outgoing Indonesian President Susilo Bambang Yudhoyono on Friday witnessed the signing of the deal delimiting the countries' Exclusive Economic Zone boundary in the Mindanao Sea and Celebes Sea. Also signed were agreements on cooperation on anti-terrorism and higher education.

Malaysian Prime Minister Najib Razak has distanced himself from growing territorial conflicts in Asia, telling a Japanese newspaper they should not jeopardize the "strategic importance" of his country's ties with Beijing.

"We must look at the big picture and not define relations with China on a single-issue basis but look at the broad spectrum of the relations, and recognise the strategic importance of our bilateral relationship with China," Najib told Thursday's Nikkei.

Three communist insurgents were killed Tuesday when police fought off an attack on their remote station in the southern Philippines, officials said.

About a hundred New People's Army (NPA) rebels attacked the police station in the rural town of President Roxas in Cotabato province on Mindanao island, said regional police spokesman Senior Inspector Aldrin Gonzales.

Several hundred Filipino and Vietnamese protesters united in a march in the Philippine capital on Friday, demanding that China stop oil drilling in disputed South China Sea waters.

Filipino riot police blocked the entrance to a high-rise building that houses the Chinese consulate in Manila's financial district as around 200 protesters marched on the office.

A strong quake struck at sea off a major island in the central Philippines on Thursday, but there were no immediate reports of damage or casualties and no tsunami warning was issued.

The U.S. Geological Survey said the 6.2-magnitude quake struck the Sulu Sea 38 kilometers (24 miles) off the southwest coast of Negros island at 6:16 pm local time (1016 GMT).

The Philippines warned on Wednesday that China may be building an airstrip on a reef in the South China Sea, boosting the superpower's claim to most of the strategic Asian waters.

Filipino surveillance aircraft have been monitoring large-scale reclamation and earth-moving activity on Chinese-held Johnson South Reef since January, the defense department said.

Muslim guerrillas from a breakaway faction have killed two soldiers in a wave of small bomb attacks in the southern Philippines, the military said Tuesday.

The blasts were claimed by the Bangsamoro Islamic Freedom Fighters (BIFF), a guerrilla faction being hunted by the military after the government signed a peace treaty in March with the main Muslim rebel group, the Moro Islamic Liberation Front (MILF).

Philippine prosecutors on Monday filed environmental crime charges against nine Chinese fishermen arrested in disputed South China Sea waters, despite Beijing's warning of a dire effect on relations.

The court case is the latest step in a simmering dispute between the neighbors in the strategically important South China Sea, which is home to key shipping lanes and is believed to harbor vast oil and gas reserves.

Scores of U.S. and Filipino marines launched mock assaults on a South China Sea beach in the Philippines Friday, as a row escalates between Beijing and its smaller neighbors over the strategic waters.

The drills, part of annual war games between the two countries, came after Vietnam said its vessels were rammed by Chinese ships protecting a deep-sea oil rig in disputed waters off Vietnam's coast.

The skipper of a Chinese fishing boat claimed Thursday that his vessel was shot at by Philippine police as 11 fishermen aboard another were seized, state media reported.

"They rushed toward us in a boat and fired at us," He Junting, captain of the Qiongqionghai 03168, said of Tuesday's events, according to the official Xinhua news agency.