NORTH COTABATO (UPDATED) - A town mayor earlier tagged by President Rodrigo Duterte as a "narco-politician" was killed in an alleged shootout in North Cotabato early Friday.

Mayor Samsudin Dimaukom of Datu Saudi Ampatuan and nine others, including his body guards, were shot dead in Old Bulatukan in Makilala, North Cotabato at 4:30 a.m.

They were brought to the Makilala Specialist Hospital and Midway Hospital for treatment but were declared dead on arrival.

Initial reports said the mayor's convoy was flagged down at a checkpoint manned by the Anti-Illegal Drugs Group and PNP Regional Public Safety Battalion 12 in Barangay Bulatukan based on information that the group would transport illegal drugs to Maguindanao and Cotabato area.

The mayor's convoy allegedly did not stop and instead fired at the operatives.

South Central Mindanao Police spokesman Superintendent Romeo Galgo said it was the convoy of Mayor Dimaukom that initiated the shootout.

"We did not initiate it. It was the law enforcers who were fired upon by the convoy, that's why we returned fire," he said in an interview on ANC's The Bureau.

Galgo added that the checkpoint had been planned since they received information that Dimaukom and his men were carrying illegal drugs.

"There was information that Mayor Dimaukom and company [were] bringing illegal drugs in the area which is why [the] CIDG (Criminal Investigation and Detection Group) conducted this planned checkpoint," Galgo said.

Authorities are still conducting investigation, as of posting time.

Recovered from the crime scene were six assorted firearms and 13 sachets of illegal drugs, authorities said.

Last September, authorities conducted a search in Dimaukom's compound in Maguindanao but no contraband was found.

• Read: PNP raids compound of alleged narco-politician

The names of the mayor and his wife, Vice Mayor Anida Dimaukom, were on Duterte's list of incumbent and retired government officials allegedly involved in the illegal drug trade. The couple denied the allegations.

--with reports from Arianne Mae Tampus Apatan, ABS-CBN News