PNP's prime suspect in the Davao blast pic.twitter.com/SP4GisajMQ

— Jeff Canoy (@jeffcanoy) September 7, 2016

MANILA - The Philippine National Police (PNP) is set to file multiple murder complaints Wednesday against a primary suspect and six other people tagged in the September 2 bombing of Davao City.

The seven suspects were identified by the victims of the deadly explosion, Davao City police chief, Senior Superintendent Michael John Dubria said.

"We have substantial affidavits ready for filing of the case," Dubria said in a press conference with other security units.

Dubria, however, said they were still investigating the affiliations of the primary suspect -- a man believed to have left the bomb at the packed Roxas Night Market.

They were also verifying if the man is still in Davao City.

Police earlier released a cartographic sketch of the primary suspect who has a slim built, is between 5'7 to 5'8 in height and is around the age of 30.

LOOK: Artist's sketch of Davao blast suspect

BLAST MASTERMIND?

Dubria also clarified that their investigation does not cover Talitay Vice Mayor Abdulwahab Sabal of Maguindanao, who is suspected of masterminding the blast.

Sabal, who was arrested outside the Cotabato Airport in Datu Odin Sinsuat on Saturday, is now under police custody at Camp Crame.

Sabal and his brother, Talitay Mayor Montasir Sabal, had been tagged as drug coddlers by President Rodrigo Duterte in August.

Dubria said the national police headquarters will look into the alleged links of Sabal to the Davao bombing.

Andanar: ASG, drug lords may be behind Davao blast

In the meantime, authorities have boosted checkpoints, intelligence gathering operations and other security checks in the city.

Col. Erwin Bernard Neri, head of Task Force Davao told the public: "We really have to cooperate to secure and save the city."

The death toll in the powerful explosion has reached 15 after an injured pregnant woman passed away on Tuesday.

The bombing also injured 60 other people, prompting President Duterte to declare a state of national emergency due to lawless violence.