Authorities are looking at the possibility that Sunday night’s explosion in Zamboanga City, which left three people killed and more than 20 injured, was a handiwork of the Abu Sayyaf.

Director Felicisimo Khu, head of the PNP Directorate for Integrated Police Operations in Western Mindanao, said initial findings indicate that the bomb, which ripped through the Atilano Pension House, was made of trinitrotoluene or TNT.

“The explosion caused a fire that gutted most of the second floor and brought down the concrete floor around the seat of the explosion,” Khu said.

The improvised explosive device (IED), which had concrete nails for shrapnels, was “similar” to those that went off at the Red Palm Pension House in Brgy. Guiwan on October 9 and at Mon’s Kitchenette in Isabela City last June 25, according to the police official.

“The type, nature, and make of these IEDs are associated with the Abu Sayyaf,” Khu said.

Investigation is focusing on a man, who checked-in as Jeffrey, and a woman who occupied Room 222 at 7 p.m. but “hurriedly left” around 9 p.m., 30 minutes before the blast, the police official added.

“Nagsasagawa pa kami ng investigation pero ang Abu Sayyaf lang naman ang nagpapasabog dito sa amin,” Chief Supt. Elpidio de Asis, Zamboanga Peninsula regional police director, said.

A total of 30 people, including three Marine soldiers, were taken to the hospital after the blast. Three, identified as Roel Barcelona, Fidel Aguias, and a certain Mariz, got killed.

Ten victims were still in the hospital as of Monday noon, including sisters Carmelita and Kristine Llanepa who are confined at the intensive care unit, Khu said.

In Manila, National Police chief Dir. Gen. Nicanor Bartolome ordered tighter security measures for the entire Zamboanga Peninsula to prevent another bomb attack.

Bartolome directed De Asis to strictly implement the “three-tiered defense plan,” which calls for intensified intelligence monitoring, target-hardening, and damage mitigation, PNP spokesman Chief Supt. Agrimero Cruz said.

The PNP chief also ordered maximum police visibility and advised the public to report suspicious persons and baggages to authorities.

The Abu Sayyaf, which is tagged by the US as a terrorist organization and is allegedly linked to the Jemaah Islamiyah, has been blamed for several bombings, kidnapping for ransom, beheadings, and attacks on government and private facilities in Mindanao.

Some of its members were reportedly involved in a clash with government troops in Basilan on October 18 that left 19 soldiers dead.

The group reportedly suffered a number of casualties, but only three were confirmed, when the military conducted air raids in the mountains of Sulu on October 30. (John Roson)

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