Maguindanao Gov. Andal Ampatuan Sr. should also be taken into custody and investigated for his possible involvement in an election-related massacre of 57 people, a member of a rival clan said Thursday.

"Sana hindi lang si Unsay, pati ang matanda isama nila (I hope not only Unsay, they should also take the [older Ampatuan])," Buluan town Mayor Ibrahim "Jojo" Mangudadatu said in an interview over radio dzMM.

Mangudadatu said they believe the provincial governor was involved in the massacre because of the presence of the provincial government's backhoe at the site of the massacre in Barangay Saniag, Ampatuan town.

The backhoe was used by the armed men to dig up two burial sites for the members of the Mangudadatu clan, including the wife of Buluan Vice-Mayor Esmael "Toto" Mangudadatu and his two sisters.

A total of 57 bodies have been unearthed from the two burial sites as of Wednesday night.

Mangudadatu said the backhoe could not have been used in the massacre without the permission of the provincial governor.

Authorities said Ampatuan Sr.'s son and namesake Datu Unsay town Mayor Andal "Unsay" Ampatuan Jr. will submit himself to Presidential Adviser on Mindanao Affairs Jesus Dureza at the Maguindanao capitol compound in Shariff Aguak on Thursday.

Dureza said Ampatuan Jr. he will be brought to General Santos City and turned over to Justice Secretary Jesus Dureza.

Earlier, the military took control of the provincial capitol and the municipal halls of Shariff Aguak and Ampatuan towns.

Armed Forces of the Philippines (AFP) spokesman Lt. Col. Romeo Brawner said the military and the police have been instructed to take physical control of the three local government buildings and other vital government installations.

The police have also suspended permits to carry firearms as part of the implementation of a total gun ban in the three areas.

Joint police and military teams have started disarming and arresting members of private armed groups and militiamen who are loyal to the Ampatuan clan.

Filing COC after burial

Mayor Mangudadatu said they were going to bury on Thursday morning the bodies of his brother's wife, Genalyn, and their two sisters who were killed along with more than 50 other people by at least 100 gunmen allegedly led by Ampatuan Jr..

Mangudadatu said his brother, Vice-Mayor Mangudadatu, will file his certificate of candidacy for governor of Maguindanao after the burial.

There were allegations that Ampatuan Jr. led the massacre to stop Vice-Mayor Mangudadatu's wife from filing his COC in Shariff Aguak on Monday.

Ampatuan Jr. was reportedly being groomed by the Ampatuan family to replace his father in the gubernatorial post.

The Maguindanao governor, his son Ampatuan Jr., and ARMM Governor Zaldy Uy Ampatuan were kicked out of the Lakas-Kampi-CMD party three days after the massacre.

Gilbert Teodoro, the party's standard bearer, said party members unanimously decided to expel the three Ampatuans from the party because of the massacre.

"We feel that they have failed to exercise their moral and actual authority over their clan members which is most probably the cause of the incident," Teodoro announced.

The announcement came after Teodoro and his running mate TV host Edu Manzano visited Vice-Mayor Mangudadatu to personally express their condolences.

The Liberal Party (LP) has said that Vice-Mayor Mangudadatu was supposed to be sworn in as their new member and endorsed by the party as its gubernatorial candidate in Maguindanao before the massacre happened.