(AFP) Malaysia will tighten security off Sabah after a Muslim revolt in the Philippines, the deputy prime minister said in remarks published today.

Abdullah Ahmad Badawi said the unrest could cause big problems for Malaysia if refugees fled the southern Philippines, where heavy fighting Monday left at least 52 people dead.

"This is what saddens me and perhaps eventually, the turn of events will bring more suffering to the Muslims in the southern Philippines," he was quoted as saying by local media.

Fighting erupted when the Moro National Liberation Front faction of guerilla-turned-governor Nur Misuari attacked and seized several security outposts in the rebel stronghold of Jolo.

Forty-eight of Misuari's followers and four soldiers were reportedly killed in the attacks, staged to prevent the holding of elections in the Autonomous Region for Muslim Mindanao.

Abdullah, who is also home affairs minister, said the government would increase security along the coastal areas but would not deploy extra soldiers at this stage.

"We are still not sure of the developments in the Philippines. However, one thing for sure is that our borders must continue to be watched by our police and military."

Patrols to continue

Muhmad Yassin Yahya, commander of the state's Fifth Brigade Infantry, was quoted by the Star daily as saying 24-hour air and sea patrols would continue, while security forces had been put on extra alert.

"All branches of the military, navy, air force amd police are keeping a close watch on our borders.

"We are not taking any chances ... we know that if there is any problem there, they (refugees) would run into Malaysian waters," he said.

In response to a question on how Malaysia could help resolve the crisis, Abdullah said the government would "remain neutral pertaining to the internal affairs of neighbouring countries and others.

"However, we will look into the matter seriously if there is a request from the Philippines government."

Both governments have previously expressed concern over violent Islamic extremist groups in their territories and possible links among them.