DAVAO CITY, Philippines ? (UPDATE 3) Two more members of a powerful clan in Maguindanao linked to the massacre in the province were now in the custody of authorities, officials said Saturday.

Maguindanao Governor Andal Ampatuan Sr. was arrested by government troops on Saturday dawn, hours after martial law took effect in the province.

Major Randolph Cabanbang, spokesman of the Eastern Mindanao Command, said the arrest was made 2 a.m. Saturday in his residence in Shariff Aguak town in Maguindanao.

"The arresting team went to his house. There was no resistance, He peacefully submitted himself," Cabangbang said.

Andal Sr. is the father of Datu Unsay town mayor Andal Ampatuan Jr., the prime suspect in the massacre of at least 57 people, most of them journalists, on November 23.

Security forces are now also holding Autonomous Region in Muslim Mindanao (ARMM) governor Zaldy Ampatuan in connection with the massacre.

Armed Forces of the Philippines Chief of Staff General Victor Ibrado said in a briefing that the ARMM governor was taken by authorities for questioning around 7 a.m. from his residence in Shariff Aguak and was now headed to a police camp in nearby city of General Santos City.

Presidential Assistant for Mindanao Secretary Jesus Dureza said the arrests would continue until "everyone who is involved in crimes will be taken in."