A private armed group led by Datu Bahnarin Ampatuan was reportedly among those involved in the killings of the SAF members . Bahnarin Ampatuan , who is also implicated in the Maguindanao massacre case , is the brother of Mamasapano mayor Benzar Ampatuan . Bahnarin and Benzar Amputuan were rivals at the 2010 Mayoral elections . Benzar expressed doubt of his brother 's participation and believes that Bahnarin would not associate himself with such groups like the BIFF nor to people like Abdul Basit Usman who made an attempt to kill Benzar 's grandfather
Maguindanao massacre
Maguindanao massacre
Mamasapano clash