The Philippine military says troops have killed 40 Abu Sayyaf extremists and wounded 25 others in two battlefronts in the first major counterterrorism offensive in the south under the new president.

Regional military spokesman Maj. Filemon Tan said Monday 22 militants had been killed and 16 others wounded in the assaults that started last week in the jungles of Sulu province. One soldier had been killed in the fighting.

Tan says 18 Abu Sayyaf fighters had been killed and nine others wounded in simultaneous offensives on the nearby island province of Basilan.

President Rodrigo Duterte has warned the Abu Sayyaf to stop a wave of ransom kidnappings, warning he would eventually confront them. His military chief said last week a looming offensive would "shock and awe" the extremists.