Philippines skull could be US hostage

Troops are on alert following bombs and heavy fighting

Philippine soldiers have recovered a skull believed to be that of a US hostage who rebels have said they beheaded.

Guillermo Sobero: Missing for months

The skull was found on top of a tree trunk on the southern island of Basilan, where Abu Sayyaf rebels are still holding at least 18 hostages.

The discovery came amid heavy fighting at the weekend in which officials said 21 rebels were killed and 17 soldiers injured.

The Abu Sayyaf says it is fighting for a separate Muslim state, but the government dismisses them as criminals who are more interested in making money from ransom demands.

The human skull has been sent to Zamboanga for testing, and is believed to be that of a Californian man, Guillermo Sobero. A pile of human bones, minus the skull, were found on Friday.

Kidnapped

Abu Sayyaf spokesman Abu Sabaya claimed in June to have beheaded Mr Sobero as an "independence day gift" to the Philippine Government. The tourist was among three Americans and 17 Filipinos kidnapped from a western Philippines resort on 27 May.

Abu Sabaya, left, said Mr Sobero was beheaded

The group is still holding American missionary couple Martin and Gracia Burnham.

Philippine soldiers were accompanied to the skull, on Kaulayan Mountain, by an alleged kidnapper, said Lieutenant-Colonel Romeo Labrador, commander of an army battalion on the island. The skull's jaw was missing.

The US embassy in Manila plans to send representatives to Zamboanga to help identify the human remains.

The rebels are still holding an American couple

Early on Monday, suspected rebels set off small bombs in three hotels in Zamboanga city, on the island. There was minor damage, but no casualties, said the military.

The US says Abu Sayyaf has links to Osama Bin Laden and his al-Qaeda network, but police said they had found no connection between the bombings and the start on Sunday of US-led air strikes against Afghanistan, which is accused of sheltering Bin Laden.

Sunday's fighting on Basilan was the most intense for several months.