The two suspects in the Bangkok blast voluntarily showed up to the police, insisting they are tour guides, authorities say.

The two men who were suspected to be part of the deadly bombing were seen in the CCTV footage as though they were covering the main suspect while the bomb is being planted.

The authorities are now questioning the pair. Police believe that there are at least 10 people involved and carefully planned the attack which killed 20 people and wounding more than 150 in Bangkok Monday night.

National police chief Somyot Pumpanmuang said he believed the attack was planned at least a month in advance.

Source: BBC News