COTABATO CITY - Government prosecutors on Tuesday filed 25 counts of murder against Datu Unsay, Maguindanao Mayor Andal Ampatuan Jr. as principal suspect in the massacre of 57 civilians in Ampatuan town last November 23.

The case was filed by an investigation panel from Manila headed by State Prosecutor Leo Dacera.

Two boxes of documents were presented before Cotabato Regional Trial Court Branch 15 Clerk of Court Umaima Silongan.

Atty. Edilberto Jamora, the panel's spokesman, explained that each count is represented by almost 40 pages of documents.

"We only filed 25 because at the time of the inquest proceedings, those were only available medical records of the victims," he said.

He added that more charges will be filed against the Datu Unsay mayor as the investigation continues.

He said the most crucial evidence presented by the panel is a phone conversation between Biliran Vice-Mayor Ismael Mangudadatu and his wife, who was among those killed in the massacre.

According to Jamora, the Court will now try to resolve if there is probable cause and eventual issuance of warrants against suspects who may be identified in the proceedings. They will also try to petition the transfer of proceedings from this region.

Justice Secretary Agnes Devanadera earlier said she will request for the transfer of venue to Manila as there are no judges in Cotabato City.

Andal Jr. belongs to the powerful Ampatuan political clan. He is the son of Maguindanao Gov. Andal Ampatuan, Sr., and brother of Autonomous Region in Muslim Mindanao (ARMM) Gov. Zaldy Ampatuan.