Datu Saudi Ampatuan, Maguindanao Mayor Samsudin Dimaukom and 9 others were killed in an alleged firefight with the police.
The incident took place in Barangay Bulatukan, Makilala, North Cotabato at about 4:30 am Friday.
Reports say, Dimaukom and his convoy of vehicles were stopped by the police at a checkpoint, following an information that the mayor’s group was bringing illegal drugs to Maguindanao and Cotabato.
As soon as Dimaukom's car slowed down, his bodyguards allegedly fired their guns at the authorities, resulting in a shoot-out.
Dimaukom was tagged by President Rodrigo Duterte in August as among local officials involved in illegal drug trade.