THE Davao City Police Office (DCPO) reported that the improvised explosive device (IED) used in Friday's night market blast was cellphone-activated.

In a press briefing at the DCPO Sunday night, police director Senior Superintendent Michael John Dubria, along with Consorcio Gerones of the Explosive Ordnance Division (EOD), showed some fragments of the IED recovered from the site of the explosion.

Dubria said a fragment, the upper portion of the device fuse assemble, as taken from one of the victim's liver.

He added that the recovered fragments point that they are part of a 60mm mortar round as compared to a mortar body.

He said the fragments are in the custody of the Philippine National Police (PNP) Regional Crime Laboratory Office-Davao while the authorities are trying to reconstruct the IED to determine its origin.

"The danger of a 60mm mortar round is that its whole body fragments upon explosion, turning into shrapnel, can cause serious injuries to the victims," Dubria told the media.

In a separate interview with the media, Task Force (TF) Davao commander Colonel Henry Robinson Jr. said the persons of interest possibly sneaked the IED in the city through coastal areas.

"It is also possible na nandito na sila nakatago lang kasi yung splinter na nakuha from the blast site ay kinakalawang na," Robinson said.

Robinson admitted that the effectiveness in terms of security have been limited due to lack of closed circuit television (CCTV) cameras in coastal areas.

"Merong area kasi na hindi pa na enhance yung ating security measures. But the city (have) already plans to place more CCTV cameras in the coastal areas," Robinson said.

Dubria said the IED was placed inside a bag and was carried by a man. He added that the man even availed of a massage in the night market before he left, including his bag unattended, and detonated the IED through a cellular phone.

PNP director Ronald dela Rosa earlier said the explosive is similar to the IED used by Abdul Manap Mentang, who was responsible in the 2005 bombing incident at the Davao City Overland Transport Terminal (DCOTT) in Ecoland.

Dubria said authorities are now hunting down a man and two women as persons of interest in the explosion. He added that they have already eight witnesses and eight CCTV camera footages that would lead them to the suspects.

But Police Regional Office (PRO)-Davao spokesperson Chief Inspector Andrea dela Cerna clarified that they are not limiting their persons of interest to three as there can be more. She added that their investigation is ongoing.

Dela Cerna said they are looking into several motives of the blast and these are disgruntled vendors, their intensified campaign against illegal drugs, political and/or terrorism.

Robinson said that among the terrorist groups the authorities are also looking into, for possible involvement in blast, are Abu Sayyaf, Al-Khobar, Maute and Al-Khalifa Philippines.

TF Davao has requested more troops following the incident, Robinson said, adding that the Eastern Mindanao Command and Army's 10th Infantry Division augmented eight officers and 200 personnel to TF Davao.

Dela Rosa said the PNP and Armed Forces of the Philippines are on full alert status. He also ordered the police to maximize police visibility and intensify security measures.