Australians travelling to Thailand have been warned to stay away from a section of Bangkok's central business district following a bomb blast that killed 22 people and injured at least 120.
The Australian government updated its travel advice on the Smart Traveller website to inform travellers of Monday night's blast, which tore through the Erawan Hindu shrine, one of Bangkok's most popular tourist attractions.
Thai authorities says they have identified suspects from CCTV footage, which shows a man placing a backpack against the fence of the shrine before walking off shortly before the explosion. 
"Today we have seen the closed-circuit footage, we saw some suspects, but it wasn't clear. We have to find them first." Prayuth Chan-ocha, the country's military chief told reporters.
Mr Prayuth said the suspects were believed to be from an "anti-government group based in Thailand's north-east" - the heartland of the kingdom's Red Shirt movement that opposes the military junta.
As Thais struggled to comprehend the scale of the carnage, an explosion was heard near the Sathorn-Thaksin bridge across Bangkok's Chao Phraya river on Tuesday afternoon. There were no reports of injuries and the source of the blast was unknown. The bridge is near the luxury Shangri-la and Mandarin Oriental hotels.
The shrine is near a number of upmarket hotels, including the Erawan Hotel and the Intercontinental, and malls including the Siam Centre and Siam Paragon.
It is next to the Ratchaprasong intersection, the site of months of anti-government protests in 2010 by supporters of ousted former prime minister Thaksin Shinawatra.
Australians are now being advised to stay away from that section of Bangkok's Chidlom district, to exercise a high degree of caution travelling in the country, and to follow the advice of local authorities.
"We continue to advise Australians to exercise a high degree of caution in Thailand," the Smart Traveller website says.
The Department of Foreign Affairs and Trade said it had not received any information to suggest Australians were among those killed or injured in the bombing, which occurred just before 7pm on Monday local time.
"The Australian embassy in Bangkok is in contact with Thai authorities to determine whether Australians have been affected," a spokesperson said in a statement.
"The Australian government deplores the attack in Bangkok. The thoughts of all Australians are with the injured and the families of those who have lost their lives."
Thai police told the Bangkok Post that the bomb was composed of three kilograms of TNT stuffed in a pipe and wrapped with white cloth. Its destructive radius was estimated at 100 metres.
Kongcheep Tantrawanich, a spokesman for Thailand's Defence Department, told the Bangkok Post that the bombing was "the work of those who have lost political interests and want to destroy the 'happy time' of Thai people".
"It's an attempt to ruin Thailand's tourism image," he said.
BANGKOK BOMBING Travellers' reactions
'I just read quickly this morning, and I'm a bit concerned about it. When these things happen it's always terrible, but ... I don't think there is going to be any more explosions"
Eduardo Checcacci, Italian tourist, departing for Bangkok
We just feel for the victims. Something like this should not happen at all in Bangkok ... We weren't really afraid, we did not feel insecure going out on the street. But I think after this it'll probably change, the mentality of the Thai people.
Annie Thatphithakkul, returning home to Bangkok
We visited around that area about four hours before, but we did not see anything. We left our hotel at about 8.30, and there was just no traffic. Everyone stayed inside. We put the TV on, and we just said 'let's get out now'. It had an eerie feeling..."
Leanne White, Melbourne-based tourist, returning home
Physically I did not see it, but we were in a taxi and the road was closed. The taxi driver had to use the back way. ... Thailand is a peaceful country. Explosions are unusual. People go there for enjoyment, for a holiday. They do not expect this."
Walr Bajawray, Melbourne-based tourist, returning home