The very clear 30-second video, from a camera in a shop near the protest, shows a man wearing a white T-shirt and a green jacket and black cap and carrying a black shoulder bag, throw an object later identified as an RDG-5 type grenade at a tent behind a rally stage of the People's Democratic Reform Committee (PDRC) about 1.30pm.
The suspect fled into Ratchawithi Soi 14 where he was chased by PDRC security guards and protesters. While fleeing, the man lobbed another grenade and fired shots from a .38 pistol, before hiring a motorcycle taxi driver to take him to Charansanitwong area in Bangkok’s Thon Buri district.
The attack left 28 people wounded, four of them seriously.
Capo asked members of the public to view the video and offered a 200,000 baht reward for information leading to the suspect's arrest.
Shortly after 5pm, the Facebook page of the spokesman team to the Royal Thai Police posted pictures of the suspect and a message saying Metropolitan Police Bureau (MPB) chief Kamronwit Thoopkrachang had increased the reward for the suspect’s arrest to 500,000 baht.
Members of the public can tip-off police by phoning or sending a text message to 1599 or e-mailing email@example.com.