National police chief Somyot Pumpunmuang said the bomb tossed from a bridge at Bangkok’s Sathorn pier and yesterday’s bombing of the Erawan shrine are the work of the same perpetrators, some of whom may be foreigners.
After inspecting the scene at the busy Chao Phraya River boat terminal, Pol Gen Somyot said divers were able to recover a half dozen metal fragments of the pipe bomb thrown from the Taksin road and rail bridge near the waterway and the BTS Saphan Taksin station.
The device bounced off a post and into the nearby Sathorn canal where it detonated harmlessly, sending up only a large plume of water. There were no injuries or damage.
Explosive ordnance disposal technicians found TNT was used in both devices, which had been stuffed into a metal pipe with a timed fuse.
Pol Gen Somyot said there were more than one person behind the two bombings and that both Thais and foreign nationals were involved.
“I can tell you now that there are not only foreigners involved in the incidents but some Thais must have taken part,” the police chief said. Foreigners, he said “could not have … walked their way onto the (Taksin] bridge. There must be Thai people involved whose hearts are not Thai.”
The Sathorn bomb was estimated to have a blast radius of 35-50 metres, less than half of the bomb left under a bench Monday night at the Hindu shrine at the Ratchprasong intersection.
Pol Gen Somyot admitted that police briefly arrested a foreign man at Suvarnabhumi airport who appeared similar to CCTV images of the prime suspect. Immigration officials initially stopped him due to a problem with his travel documents and released him so that he could fix it. He has not been allowed to depart Thailand for the time being.
Police would not rule out he was the same man who appeared in the Erawan CCTV footage and are investigating further.
The police chief asked the public to send tips to authorities if they see someone they suspect was the man seen wearing a yellow shirt and leaving a backpack at the Erawan blast site.
The Sathorn bombing took place at 1.20pm, but half the pier remained open with boat operations continuing as normal. Police closed Sathorn Road to traffic from the pier to the Saphan Taksin Skytrain station to investigate.
Assistant police chief Prawut believed the perpetrator wanted to throw the bomb onto a busy walking platform leading to the pier but missed. CCTV footage taken at the time of the explosion showed people running down a causeway over the canal to escape the blast.
Police initially dispatched divers into the canal to try to recover any surviving pieces of the bomb that Transport Minister Prajin Juntong called an "improvised explosive device". Later, sandbags and pumps were brought into to drain the impact area to hasten the search for evidence.
Sathorn pier is a major terminal linking Chao Phraya River commuter boats and the nearby Skytrain station. It's also a major tourist stop, especially for Chinese tour groups.
ACM Prajin said the Sathorn bomb was an IED that was thrown. An IED is also blamed for Monday's devastating explosion at the Erawan shrine that officially has left 20 dead and 125 injured.
A security camera captures the moment of explosion in Sathorn area.