Philippine security troops were battling their way into coastal villages where members of a rebel faction of the Moro National Liberation Front (MNLF) have held scores of residents hostage, Sky News reported citing government officials.
Interior Secretary Mar Roxas said government forces surrounding around 200 rebels have slowly started retaking rebel-held areas and clearing roads in the coastal outskirts of Zamboanga.
Military spokesperson Lieutenant Colonel Ramon Zagala said the trrops have not resorted to heavy artillery fire, rockets or launched airstrikes as unspecified number of hostages are still held by the rebels.
Of all those killed, 47 were from the rebel ranks, officials said. The rest include nine civilians, two soldiers and three policemen.
Philippine security troops were battling their way into coastal villages
The rebels have reportedly detonated bombs to set several houses on fire to slow the troops' advance.
Several hostages have escaped but it remained unclear how many remained in rebel custody.
The Muslim rebels took scores of people hostage in Zamboanga city Monday after government troops prevented them from raising their flag at the city hall.
The MNLF used to be the largest Muslim rebel group seeking a separate state in Mindanao until it dropped secessionist demand and settled for limited autonomy under a signed agreement in 1996.
But many of its guerrillas held on to their firearms and periodically staged rebellions in the past, complaining the government has reneged on its promise to fully develop impoverished Muslim regions.