A Philippine military official says a roadside bomb has exploded and wounded seven soldiers aboard a passing army truck in the latest of a series of explosions that has set off a security alarm in the country's volatile south.

Muslim guerrillas belonging to the rebel faction the Bangsamoro Islamic Freedom Movement, claimed responsibility for the attack Wednesday near Shariff Aguak town in Maguindanao province, where army troops have engaged the insurgents in recent clashes.Regional military spokesman Col. Dickson Hermoso says another bomb made from a mortar round went off before dawn in Midsayap town in North Cotabato province near Maguindanao, damaging some stores but causing no injuries.On Monday, a powerful bomb rigged to a van killed eight people and wounded 31 others in Cotabato city, also near Maguindanao.