An ongoing investigation has revealed that the latest bomb attack on the Criminal Court is part of a plot to stage violent acts in Thailand - in a bid to get the United Nations to intervene.
"[The perpetrators] hope the UN will send in officials to control the situation here," bomber Yuttana Yenpinyo allegedly told police and soldiers after his arrest.
Speaking from a hospital, Yuttana has confessed that he was paid Bt20,000 (S$848) to throw an RGD5 bomb into the Criminal Court on Ratchadaphisek Road in Bangkok on Saturday night.
He and accomplice Mahahin Khunthong allegedly threw a hand grenade at the court, but were arrested shortly after. Both are 34 years old.
In response to intelligence reports that some extremist and anti-government groups were preparing to carry out attacks at several locations including the Criminal Court, plainclothes soldiers were deployed around the Criminal Court.
When the bomb went off, the soldiers were well positioned to make the arrests.
Mahahin, who was riding pillion at the time, allegedly opened fire in a bid to escape. Soldiers shot back, hitting the driver four times.
Mahahin scaled a wall leading into a nearby housing estate but was quickly apprehended. He had a gun and a tablet on him. Police and soldiers searched the motorcycle the suspects used and found a buy-and-sell agreement for the vehicle identifying Yuttana as the owner.
But according to its registration paper, it belongs to a man living in Bangkok's Nong Chok district.
Police will summon the man to determine if he is involved in the bomb plot.
The examination of Mahahin's tablet revealed the Line chats between him and a person going by the name of "Deer" and using a woman's photo as the profile picture.
"The communications between the two have mentioned the plot of carry out attacks," a source said.
His communication with another person via the Line social network provided authorities with crucial evidence in their bid to track down masterminds behind the attacks and other people linked to them.