By Sarah Toms
BBC News, Manila
The Philippine military says five members of the Muslim group the Abu Sayyaf have been killed in fierce fighting in the south of the country.
Troops are searching for several key militants
Rockets have been fired and bombs dropped on a base of suspected members of the Abu Sayyaf on Jolo island.
The army says five soldiers were wounded and a civilian guide was killed in the clashes, which started on Tuesday.
The casualties cannot be independently confirmed.
Heavy fighting broke out on Jolo after soldiers caught up with militants fleeing the air strikes on their camp.
The Philippines is trying to stop Abu Sayyaf and members of Jemaah Islamiah, a regional network with alleged links to al-Qaeda, from using Jolo as a base to train militants and plot bomb attacks.
The United States believes two main suspects in the 2002 Bali bombings - Dulmatin and Umar Patek - are also hiding in the south. The Philippine military says it is confident it will flush them and Abu Sayyaf's leader, Khaddafy Janjalani, out of Jolo.
Abu Sayyaf is the smallest of four Muslim rebel groups in the Philippines with around 400 members.
Muslim separatists have been fighting in the south since the 1960s for greater independence from the mainly Catholic government in Manila.
The conflict has killed over 120,000 people and stunted development in the area, which is rich in natural resources.
The government is in peace talks with the largest rebel group, the Moro Islamic Liberation Front.
But it wants to destroy the Abu Sayyaf, which is blamed for the country's most deadly militant attack - the bombing of a ferry in 2004 that killed more than 100 people.