MANILA, Philippines — Finding no traces of bomb chemicals through the debris, probers of the powerful explosion that ripped through a posh apartment building in Taguig City on Friday night, started looking into the building’s possible engineering issues.
“We are setting up protocols and procedures on how to check up the utility pipes of the building. These are (where the building’s get their supply of) electricity, gas and water,” Interior Secretary Manuel Roxas told reporters outside the Two Serendra, a plush apartment building in Bonifacio Global City in Taguig where in one unit on the fifth floor a blast had knocked down the walls.
The explosion that happened around 8 p.m. on Friday sent a slab of concrete flying across the farthest side of street, crushing a passing delivery van and killing three people in it. Five others, including the tenant of Unit 501B, were injured.
In a statement e-mailed Sunday, Roxas said that “probers who sifted through the debris and analyzed burn patterns from concrete slabs found no positive traces of bomb chemicals.”
He said that even the bomb-sniffing dogs of the police did not give them a signal that could point to bomb residues or fumes.
“We are eliminating possibilities one by one… What we have is significant but insufficient to rule out bombing (as the cause of the explosion)” Roxas said.
Agencies such as the Scene of the Crime Operatives and other units of the Philippine National Police, the National Bureau of Investigation, the Bureau of Fire Protection and engineers of the developer Ayala Land were part of the investigation, which Roxas said should be scientific, thorough and extensive.
On Sunday, experts from the Department of Science and Technology joined the investigation with the Undersecretary for research and development Amy Guevarra attending the Sunday’s closed-door case conference.
Roxas said the investigators sought the help of the DOST in answering their questions through chemistry and physics.
“We want to find out what kind of explosion can propel this heavy slab of concrete that far?” Roxas said echoing what the investigation, which started on Friday, has been hoping to answer.
The probers were hoping to calculate how heavy was the slab of concrete that flew across the street and how much and what kind of force can propel it, he said.
The explosion was so powerful it had immediately ripped the walls from its ribars, Roxas said.
Investigators had also started taking statements of occupants of the third and fifth floors of Two Serendra as all angles were being explored by the police, Roxas said.
Late Saturday afternoon, the McKinley Parkway Road and portions of a shopping mall’s parking lot adjacent to the Serendra complex that was cordoned off Friday was opened to the motorists and the public.
“Police and fire authorities have thoroughly sifted through the debris scattered at the street portion and concluded the gathering of forensic evidence there,” Roxas said.
The investigators were particularly interested in Angelito San Juan, the renter at the Unit 501B, where the explosion took place.
“He is a person of interest. He was the one at the unit during the explosion,” Roxas said.
Roxas said San Juan was reported to be in stable condition but was still unable to speak to the investigators as he remained confined in the intensive care unit of the St. Luke’s Medical Center in Global City.
The DILG chief, who was the only person allowed to speak to the media about the ongoing investigation, said the police have been working on the profiles of San Juan and the owner of the unit identified as George Cayton, an overseas worker.
San Juan was on his way out of the unit he was renting when the explosion took place, probers said. He had complained to the building administrator that he was “suffocating” inside the apartment despite having the air-conditioning on.
Police have evacuated residents of building B and two adjacent buildings at Two Serendra as their power, water and gas utilities have been turned off while the investigation is ongoing.
A source said investigators have been scouring the blast site and the entire building and finding no single trace of explosive chemicals, bomb shrapnel, or any part of a device that can trigger an explosion.
So now, the investigation has focused on “the more technical issues of the building,” the source said.
On his Twitter account, Roxas posted on Sunday that a team from the DOST and the UP National Institute of Geological Sciences has also joined the investigation.
“(They are) now inspecting site with a special equipment to check if there is gas accumulation or leak in the building, Roxas said in his Twitter handle @MARoxas.
Public Works and Highways Secretary Rogelio Singson was also seen entering the Two Serendra premises on Sunday afternoon.
Roxas said the DPWH was tasked to begin a structural assessment on the building upon the completion of the investigation by the Scene of the Crime Operatives and the Bureau of Fire Protection.