THAI Police have named a man in connection with the Bangkok bombing that killed 20 people.

Authorities have revealed they are searching for a Muslim man called Mohamad Museyin, The Times of London reported.

But the bespectacled man, who was seen leaving a back pack at the Erawan Shrine shortly before the explosion, remains on the run.

News_Image_File: Suspect ... Thai police have released a sketch of Bangkok bombing suspect. Picture: Royal Thai Police

There are fears he may have fled overseas after being dropped off by a motorcycle taxi driver at Lumpini Park, in central Bangkok after the attack on Monday night.

Two other suspects who were identified on security footage and believed to be accomplices have been questioned and cleared by police.

The motive behind the attack remains unclear.

Police have said the bombing was not linked to any terrorism group, and no-one has so far claimed responsibility for the deadly blast that also injured 125 people.

The reward for information leading to an arrest has doubled to 2 million baht ($76,000), as police hope for more help from the public.

News_Image_File: Answering questions ... Two suspects, circled, were close to the main suspect, in yellow, before the bombing in Bangkok and have handed themselves into police. Picture: Supplied

Police suspect up to 10 people were involved in the attack that may have taken a month to plan.

The Australian Federal Police have sought images from who were on a flight from Thailand to Sydney this week.

They have also offered to help local authorities in their hunt for the bomber but the Thai Police had not accepted the assistance.

Australia’s Ambassador to Thailand, Paul Robilliard, offered his condolences to the Thai people at a trade dinner in Bangkok on Thursday night.

South Australian Premier Jay Weatherill, who was also at the dinner to encourage trade to his state, also expressed his sorrow.

News_Image_File: Mediation ... people pray in front the reopened Erawan Shrine. Picture: Nicolas Axelrod/Getty Images

The Thai Government attended a religious ceremony at the shrine on Friday morning.

Representatives of the Buddhist, Muslim, Christian, Hindu and Sikh religions were there.

Doves were also released as prayers for the dead and injured continued.

stephen.drill@news.com.au

@steveheraldsun