MANILA - Authorities are studying closed circuit television (CCTV) camera footage and witnesses' account as investigation on Friday's huge explosion in Davao City continues.

In a press briefing Sunday, Sr. Supt. Michael John Dubria, Davao City Police Office director, said investigation showed that the improvised explosive device (IED), which killed 14 people and wounded at least 60 others, was carried by a person inside a bag to the night market.

"We are in the process of investigating all the circumstances but in general, I can give you, that this improvised explosive device (IED) was carried by one person inside a bag, who availed of a massage service... that person left hurriedly, and we believe that the improvised explosive device exploded pag-alis nung tao," he said.

He added that the explosion occurred immediately after that person left the scene.

"It's a very short span of time, it doesn't cover an hour siguro," Dubria added.

According to Dubria, police already have an artist sketch of the persons of interest but have no clearance yet to release them.

He also said everything is still being investigated, including the cause of the explosion. Witnesses also said there are at least three persons of interest who were acting suspiciously, leaving the scene hurriedly before the explosion.