Eleven Islamist militants were killed on Friday in a gun battle with government troops in the southern Philippines, a regional military spokesman said.
Seventeen soldiers were also injured in the clash in Patikul town on Jolo Island, where the militants beheaded a Filipino hostage two days ago, said Major Filemon Tan.
The troops were on patrol when they encountered a group of about 100 members of the Abu Sayyaf terrorist group, he said.
Among those killed was a junior leader who was allegedly involved in the kidnapping of two Canadians, a Norwegian and a Filipino on the southern resort island of Samal in September.
The two Canadians John Ridsdel and Robert Hall were executed in April and June after a ransom was not paid, while the Filipino was freed in June.
The rebels are still holding captive Norwegian Kjartan Sekkingstad, five Malaysians, eight Indonesians, a Dutchman and several Filipinos.
On Wednesday, Abu Sayyaf beheaded 18-year-old Patrick Jhames Almodavar after his family failed to pay a 1-million-peso (22,000-dollar) ransom.
Philippine President Rodrigo Duterte has directed the military to crush Abu Sayyaf and also warned that the group could be a source of recruitment for the Islamic State extremist group.
On Thursday, Duterte said he was informed that a 50-million-peso ransom has been paid for Sekkingstand but the Abu Sayyaf kept on postponing his release.
“My orders to the police and armed forces against enemies of the state: seek them out in their lairs and destroy them,” he said. “The Abu Sayyaf, destroy them, period.”