Manila - A Philippine military official says suspected hard-line Muslim rebels have detonated bombs but failed to topple a high-voltage power transmission tower in the country's south.

Regional military spokesman Lt. Col. Dickson Hermoso says suspected Bangsamoro Islamic Freedom Movement gunmen rigged four bombs fashioned from mortar rounds at the base of the steel tower in a mountain village in Sultan Kudarat town in Maguindanao province late Saturday. Three of the bombs went off and damaged the tower, but it failed to collapse or cause a power outage.

Hermoso says the desperate rebels are resorting to acts of economic sabotage to try to derail a looming government peace deal with the main Muslim rebel group, the Moro Islamic Liberation Front.

Philippine troops killed 52 of the hard-line rebels in a recent offensive.