Updated

Philippine military officials say hundreds of troops have launched an assault on a southern jungle camp belonging to Abu Sayyaf militants in a bid to rescue two kidnapped coast guard personnel and other hostages, sparking a two-hour clash in which up to 15 militants may have died.

Army Brig. Gen. Alan Arrojado says no military personnel were killed in the assault Wednesday on more than 100 militants in a mountainous hinterland near Indanan town in Sulu province. The government troops fired artillery shells to prevent gunmen allied with the militants from reinforcing them.

Sulu military spokesman Capt. Anthony Bulao said the fighting eased by nightfall without any hostage being freed.

The Abu Sayyaf has been weakened by years of U.S.-backed offensives but remains a security concern.