Police said Monday they have arrested another suspect, allegedly involving in a bomb attack near headquarter of the Bhum Jai Thai Party.
Police claimed that Suriya Bhumwong, 39, was arrested in the northern province of Chiang Mai on Sunday and was later taken to Bangkok.
Police claimed Suriya confessed that he assembled the bomb and put it in a gas cylinder. He however said he did not know when and how the bomb would be used.
Detectives from the Department of Special Investigation (DSI) Monday morning are questioning the suspect and will take him to a re-enactment in the afternoon at the home of Varissareeya Boonsom, another suspect who is now in police custody.
Suriya will also be taken to the Bhumjaithai Party head office for a re-enactment.
Police have so far arrested six out of seven identified suspects with outstanding warrants for their involvement in the bombing. The last is Samran whose family name is unknown is still at large.
A bomb hidden in a fruit pushcart was remotely detonated near the Bhumjaithai party head office on June 22, seriously wounding Anek Singkhuntod, the cart vendor.
Police detained Anek after he confessed to being hired to park his pushcart close to the Bhumjaithai Party office.
Several days later, two red shirts security guards alleged to be behind the bombing were detained in Chantaburi and Chonburi respectively.
Cambodian officials arrested Varissareeya Boonsom and Korbchai Boonplod, another two suspects in the bombing who fled to the neighbouring country just one day after the incident and handed them over to Thai consular officials in Phnom Penh early July.