Maguindanao del Sur, March 1 -- Police authorities here are tracking down two men believed to be responsible for the ambush and killing of two others on the national highway in Shariff Saydona Mustapha town, Maguindanao del Sur, on Thursday afternoon.

In an interview on Friday, Col. Roel Sermese, Maguindanao del Sur police provincial director, said several persons of interest are now being sought for their possible involvement in the 4 p.m. ambush.

Killed were Rashied Lumanggal, 40, of Barangay Mirab, Upi town; and Nasrudin Alim of Kabuntalan town, both in Maguindanao del Norte.

"We are pursuing some leads, our investigation is continuing," Capt. Waldy Bunag, Shariff Saydona Mustapha police chief, said Friday regarding the ambush.

Bun...