Abu Sayyaf insurgent group active in Philippines killed six soldiers in the southern part of the country on Sunday despite a new army offensive against the Al Qaeda-linked group.

Abu Sayyaf insurgent group active in Philippines killed six soldiers in the southern part of the country on Sunday despite a new army offensive against the Al Qaeda-linked group, a military spokeswoman said.

The soldiers were patrolling in the strife-torn island of Basilan when they were attacked by about 20 heavily-armed fighters.

The incident came despite a military offensive that was launched over the weekend against the Abu Sayyaf in the island of Jolo, 129 kilometers (80 miles) from Basilan.

On Saturday troops battled about 60 Abu Sayyaf fighters in Jolo and used helicopter gunships to blast their positions, the military said.

Regional military spokeswoman Captain Rowena Muyuela said soldiers on the ground in both Basilan and Jolo had reported casualties among the Abu Sayyaf but could give no exact figures.

The heavily-forested islands of Basilan and Jolo are known strongholds of the Abu Sayyaf, which was set up in the 1990s with seed money from Osama bin Laden's Al-Qaeda network.

It has been blamed for the worst terror attacks in the country's history including bombings and mass kidnappings of Christians and foreigners. It also engaged in extortion and banditry, demanding huge ransoms for its kidnap victims.

Last month the group released two German hostages it had held for six months. It is believed still to be holding several foreign and local hostages.

The Abu Sayyaf recently pledged allegiance to the so-called 'Islamic State of Iraq and the Levant' terrorist group, although the military and government officials say this is merely a propaganda move to raise their profile.