Philippine raid kills 16 Abu Sayyaf militants

ZAMBOANGA, Philippines -- Philippine soldiers have killed at least 16 suspected Muslim guerrillas in a three-day raid that began on Friday.

Troops are now searching for the rest of the Abu Sayyaf militants, who escaped a raid on their compound on the southern Philippine island of Jolo.

Philippine troops used helicopter gunships and mortars in their attack, part of an ongoing offensive against the group, which is notorious for kidnappings, piracy and bombings.

The group -- which U.S. and Philippine officials have linked to Osama bin Laden's al Qaeda terror network -- has killed scores of people and scared away investors and tourists.

The United States is providing weapons and training to crush the Abu Sayyaf fighters, a loose band of a few hundred men in Jolo and Basilan islands.

U.S. help

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Joint operations between the two countries were officially launched on Thursday, in what is being seen as the most significant expansion of the war on terrorism since the military campaign in Afghanistan.

Some 650 U.S. troops are expected to take part in training and advising the Philippine military in its fight against the Abu Sayyaf.

But U.S. forces were reportedly not involved in the weekend raid. No government casualties have been reported so far.

Jolo is southwest of Basilan island, where the Abu Sayyaf is believed to be holding three hostages, including Kansas missionaries Gracia and Martin Burnham and a Filipino nurse.

Last year the group beheaded another American hostage.

However, critics say they fear the U.S. troops are merely the thin end of the wedge leading to a permanent American military presence in the country.

The constitutional legality of the American military deployment has been fiercely debated among Philippine lawmakers and several protests have been held outside the U.S. Embassy in Manila.

According to the Philippine constitution, overseas troops are not allowed to enter into combat on Philippine soil unless under a formal treaty.