One marine was killed and three were wounded during the assault
A senior Islamic militant was among six killed in an assault by Philippines troops on a rebel camp on the southern island of Jolo, officials say.
Abu Sayyaf commander Albader Parad was wanted for the abduction of three Red Cross workers on the island last year.
Gen Benjamin Dolorfino said his death was a "big blow" to the group.
Abu Sayyaf has been blamed for bombings, beheadings and kidnappings of Filipinos and foreigners. It has been accused of links with al-Qaeda.
"We have confirmed that one of the six bodies found belonged to Albader Parad as confirmed by independent civilian sources," said Gen Dolorfino.
"We consider it a big blow on the cause of Islamic militants in the south."
He said Sunday's raid was carried out after tip-offs from local residents.
One marine was killed and three were wounded during the assault.
Abu Sayyaf is the smallest and most radical of the Islamic separatist groups in the southern Philippines.
Its stated goal is an independent Islamic state in Mindanao and the Sulu islands. The government refuses to hold any form of talks with the rebels.
Philippine officials said in December 2009 that they had arrested an Abu Sayyaf founder - Abdul Basir Latip - who has allegedly been involved in kidnapping foreigners and Christians.
He has also been accused of forging links between Abu Sayyaf and other militant Islamist groups, such as Jemaah Islamiah and al-Qaeda.