[A police officer examines the surroundings after a powerful explosion suspected to have been caused by a faulty appliance ripped through a residential building in upscale Bonifacio Global City in Taguig, May 31, 2013, killing three people in a passing delivery van that was hit by debris, authorities said. The explosion punched a large hole in the wall of an apartment building and sent concrete chunks flying onto the street below, killing three people on board a passing van. AP/Bullit Marquez]

MANILA, JUNE 10, 2013 (PHILSTAR) By Dennis Carcamo - Interior and Local Government Secretary Mar Roxas (photo at left) on Friday said that the blast that ripped through a unit at Two Serendra condominium building in Taguig City was "mostly likely" caused by a liquefied petroleum gas (LPG).

"The explosion was not caused by a bomb," Roxas said earlier in the press conference at the Philippine National Police main headquarters in Camp Crame, Quezon City.

After a brief lecture from Dr. CP David, who is part of the investigating team from the University of the Philippines and the Department of Science and Technology, Roxas declared that it was "consistent with" a gas explosion and it is "most likely" caused by LPG.

The posh condominium community has a centralized liquefied petroleum gas system, which its developer -- Ayala Land -- had assured is safe.

David enumerated six characteristics of the Two Serendra explosion that made it consistent with a gas explosion. These are:

1. minimal post-explosion residue
2. no blast cratering
3. instantaneously dissipated flames
4. minimal charring
5. powerful and widespread pressure wave
6. almost instantaneous explosion

The blast ripped a big slab of concrete wall from Unit 501-B of the condominium building and sent it crashing onto a closed delivery van passing by McKinley Parkway Road on Friday night last week.

The van's driver, Salimar Natividad and two helpers -- Jeffrey Umali and Marlon Bandiola -- were immediately killed.

Five more people were wounded including the unit's tenant, 63-year old Angelito San Juan, who sustained second degree burns in 72 percent of his body. San Juan is still confined at the intensive care unit of the St Lukes Medical Center at the Bonifacio Global City.

Roxas said at the press conference that San Juan, who has been living in the United States for 40 years, has no criminal records.

The investigators had described San Juan as a "person of interest."

'Not a suspect'

Roxas clarified during the press conference that the police investigators never treated San Juan as a suspect.

"Kung di sya suspect noon, lalong hindi sya suspect ngayon," Roxas said, noting that the behavior and movements of San Juan were all "considered normal."

San Juan will be interviewed by investigators if he recovers from his injuries and able to talk.

Roxas said that they have been informed that San Juan is conscious, but he is under sedation and he can't talk because he is currently intubated.

He said policemen were still on standby at the hospital so they can immediately get San Juan's statement once he is able to talk.


Roxas said the investigation on the blast has been meticulous, employing six investigative tools to get to the findings.

He said that among the tools were a canine walk-through in which bomb-sniffing dogs were used to detect any trace of bomb substances and chemicals and the swabbing of the concrete slab and walls of the Unit 501-B.

He said that all of the investigative tools yielded "100 percent" negative of bomb residue.

Investigators also conducted 61 interviews of persons on the blast.

He said members of the investigating team also looked into the possibility that flammable chemicals triggered the explosion, but failed to find any traces of large containers in which these substances could be stored.

During the press conference, Roxas also showed slides of the layout or the schematic of the entire Two Serendra building and how the gas pipes are placed inside the units.

Roxas said the investigators have yet to determine the source of the gas leak inside the building.

He also noted that there were no signs of shrapnel cuts into the walls of the unit.

"Wala po yung tadtad ng shrapnel, o walang is more pushing, pressure waves ang nangyari po dito," he said.

He said members of the inter-agency task force are also looking if the changes in the interior of the walls during a recent renovation of the unit caused the gas leak.

"[Ginalaw] ang interior walls pero tsini-check pa rin kung yung lang ang ginawa nila," Roxas said, referring to the expansion of the unit's living room.

"May pahintulot ang renovation, may sinabmit na work program; ang tanong dun kung dun lang sila nag-limit sa work program o may ginawang iba?" he added. with Louis Bacani

Chief News Editor: Sol Jose Vanzi

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