At least 43 people – including 23 soldiers and 20 militants – have been killed in clashes in the southern Philippines, an army commander says.
Maj Gen Benjamin Dolorfino said 400 troops launched coordinated attacks on a camp belonging to Abu Sayyaf rebels on the southern island of Basilan.
He said soldiers recovered home-made bombs and 13 high-powered firearms.
Fighting has ceased, but troops were combing the area to see if two targeted Abu Sayyaf chieftains had been killed.
The rebel leaders were named as Khair Mundus and Furuji Indama by the Associated Press news agency, citing military officials.
The Abu Sayyaf group was once linked to regional Islamist networks, but has recently become better known for criminal brutality and high-profile kidnappings, mostly targeting Christians and foreigners.
In January, militants kidnapped three staff members of the International Committee of the Red Cross.
Two were freed in April, while the last hostage, 62-year-old Italian Eugenio Vagni, was released in July after being held for nearly six months.