Police have arrested five suspects in connection with the five bombings at Silom intersection on Thursday night.
One of the suspects is a former military officer.
The suspects were arrested at Robinson department store. They are now being interrogated at Thung Maha Maek police station, the reports said.
Jaturon Noppakit, a suspect, said he was travelling from Wongwian Yai to join the red-shirt protesters in Silom but insisted he was not involved with the bomb attacks.