American troops traveling in a Philippine army convoy came under fire this week from suspected Muslim militants on southern Jolo island but there were no casualties, the US Embassy reported on Thursday.

Philippine marines and police said the convoy of military vehicles was on its way to inspect an infrastructure project in Indanan town on Tuesday when six militants from the Al-Qaeda-linked Abu Sayyaf group opened fire.

Embassy spokesman Rebecca Thompson said only one US military vehicle was in the convoy and there were no casualties on either the American or Philippine side.

She did not provide other details.

Regional police director Bensali Jabarani, however, said a militant was killed in the clash.

On Thursday, President Gloria Macapagal Arroyo cancelled a planned trip to Jolo, but her officials blamed bad weather.

A day earlier, government forces announced the arrest of a suspected Abu Sayyaf bomber accused of being behind a failed attempt to bomb Jolo airport.

Several dozen US troops are stationed on Jolo to provide humanitarian assistance to civilians as well as counter-terrorism support to Filipino forces battling the militants. But they rarely have come under attack and are tightly guarded by Philippine troops whenever they venture out of their camp, which is inside a Philippine military base.

Still, there have been consistent intelligence reports from the Philippine police and military indicating the Abu Sayyaf may be planning attacks on American troops in Jolo.

Their presence in the Philippines since 2002 has been a sensitive issue, and they are prohibited by the Philippine Constitution from any combat roles.

The attack highlights the vitality of the Abu Sayyaf, which consists of about 300 militants notorious for kidnappings, beheading hostages and bombings and is on the US list of terrorist groups.

They have been crippled by US-backed military offensives but continue to be a threat in the country’s volatile south.

Major-General Benjamin Dolorfino, who heads the 8,000-strong Philippine marines, recently praised the US military’s non-combat assistance, particularly the rapid provision of tactical intelligence, for having helped prevent terror attacks. — AP