Video provides possible Bangkok bombing clue

As Thai authorities said on Saturday that much progress was being made in their investigation into the deadly bombing in central Bangkok that killed 20 people, a new surveillance video has surfaced offering a possible clue to solving the crime.
Col. Winthai Suvaree, a spokesperson for Thailand's ruling junta, confirmed media accounts that closed circuit television had captured the transportation route the suspected bomber took to and from the site of Monday evening's rush-hour attack and said a police sketch of the suspect had been distributed to border posts.
Virtually no other details of the suspect have been made public. A military spokesperson has said a connection to international terrorism seemed unlikely, though he offered no clear alternative theory.
Meanwhile, a new surveillance video leaked to Thai media adds more questions than clarity to the case.
It shows a man in a blue shirt placing a bag on a riverside walkway, then kicking it into the water on Monday night shortly after the deadly bomb blast, which occurred several kilometers away at the popular Erawan Shrine. About 18 hours later, at 13:00 on Tuesday, an explosion took place at the same riverside spot near a busy pier, causing no casualties.
Police spokesman Prawut Thawornsiri said Saturday that police were seeking the man for questioning, even though it remains unclear whether his actions had anything to do with either explosion. Asked if the man was a suspect, he said he was "more like a witness."
"The thing he kicked in the water might just be garbage. We don't know yet," Prawut said. Asked if the man in the video was linked to the bombing at the shrine, he said police had not yet drawn that conclusion.
Much of the police investigation, and the media frenzy surrounding it, has been fuelled by closed circuit television footage, often too blurry to distinctly identify its subjects. Prawut expressed irritation over the latest video being circulated. "The footage cannot be relied on (as evidence). It wasn't released by officials and should not be publicised," he said.

The suspected bomber, for whom an arrest warrant has been issued, was seen leaving a backpack at the spot where the bomb went off and then departing minutes before the explosion. Two men who stood nearby looked suspiciously like co-conspirators, but made themselves known to police and have more or less been cleared of any responsibility. A woman in a black shirt also seen standing nearby is being sought.
Police have released a sketch of the suspect — depicting him with eyeglasses and bushy, black hair — and offered a reward that on Friday was raised to 3 million baht ($85,000).
After initially being criticized for sending confusing messages, authorities have appeared more guarded in their statements.
On Saturday, Winthai, the military spokesman, said information would be made public once it was no longer needed to be kept secret as part of the investigation.
Theories abound as to who was responsible for the attack. They include ethnic Uighurs angry that Thailand repatriated to China more than 100 of their countrymen who had fled from there; Islamic separatists who have been carrying out an insurgency in southern Thailand for a decade; frustrated supporters of former Prime Minister Thaksin Shinawatra angry at the military government that opposes his return to politics; and rival factions within the army contending for power.