Two officials of the Philippine Coast Guard (PCG) were freed during a military offensive in the country's southern region, an official said on Thursday.
PCG spokesperson Armand Balilo said officers Rodlyn Pagaling and Gringo Villaruz were rescued after an attack but did not provide details of the operation, EFE news agency reported.
Pagaling and Villaruz were kidnapped on May 4 in Dapitan city, in Mindanao island, along with Rodolfo Baligao, a member of the local government. Baligao's decapitated body was found last week after negotiations between his family and the terrorists broke down.
"We killed 15 rebels and wounded an undetermined number as they withdrew deep into the jungles," a military official said, adding they fought about 100 Abu Sayyaf militants near the town of Indanan.
The authorities have not provided any information on the 10 other hostages, which include two Malaysians and a Dutch, who remain captive in the hands of Abu Sayyaf.
The group, formed in 1991, has conducted the bloodiest attacks and numerous kidnappings in the Philippines.
It has also pledged allegiance to the Islamic State and collaborates with Yemaa Islamiya, the Al Qaeda branch in Southeast Asia.