Bangkok: A wave of explosions and fires have hit southern Thailand only hours after twin bombs ripped through a tourist bar area in the beach resort town of Hua Hin southwest of Bangkok, killing a woman and injuring 23 others. At least four people have been killed in total and many others injured in in 12 hours of terror. 

As Thais marked the 84th birthday of Queen Sirikit, there were reports of two more bomb blasts on Phuket, the most popular destination in Thailand for Australians, and Surat Thani on the Gulf of Thailand. Unconfirmed reports said one blast was at Loma Park in Patong, an area on Phuket Island where there are hotels popular with Australians. Another reportedly exploded at a police box on Patong's main beach road, at the intersection with Soi Bangla .

Patong on Phuket Island after the explosions. Photo: Supplied

The first reports said one person was killed and many injured during a blast near the Surat Thani police station shortly after 8am, Thai time on Friday morning.

The blast outside the Surat Thani police station came moments after the daily ritual of playing the Thai national anthem. Thai media reports there was also a second explosion in Surat Thani around 8am on Friday. 

A Department of Foreign Affairs and Trade spokesman said they are currently seeking to confirm if any Australians are caught up in the bombings.

The violence has shattered hopes that volatile Thailand was finally on a path to stability after Thais voted in favour of a military-based referendum last Sunday. 

After one explosion on Phuket. Photo: Supplied

Prime Minister Prayut Chan-o-cha on Friday urged people not to panic.

"Economic and tourism is improving. Who [do you think] does not want the good things happening in Thailand? Please find out for me," he told reporters. 

Emergency services at the scene of a bomb attack in Hua Hin, Thailand that happened early on Thursday, August 11, 2016. Photo: AP

"We have to help calm people down so that they will not become panicked and that they will remain good hosts to foreign tourists," he said. 

Earlier, deputy prime minister Prawit Wongsuwan told reporters he believes one group of people are responsible and insisted they were not linked to Thailand's long-running Muslim insurgency in the country's southern provinces.

If insurgents are responsible it would mark a change in their strategy which has been to confine their conflict to their own provinces. 

In the military's government's first comment on the attacks deputy prime minister Prawit Wongsuwan told reporters he believed one group of people are responsible and insisted they were not linked to Thailand's long-running Muslim insurgency in the country's southern provinces.

The twin bombs in Hua Hin ripped through a tourist bar area at one of Thailand's top tourist destinations over night. The bombs killed one woman and injuring 23 people, three of them seriously. 

The bombs that exploded 30 minutes apart had been hidden in plant boxes outside beer bars in Soi Bintabat, near the town's main intersection.

A food cart operator was severely injured in the first blast outside a beer bar at 10.20pm Thai time Thursday (1.10pm Melbourne time) and died later in hospital.

"I heard people shouting 'bomb, bomb' but I didn't hear any blast," said Briton Mark Gainsford.

"I ran out to see if I could help. I saw eight to 10 people injured on the floor. The police arrived very quickly," he said.

Police said the bombings clearly targeted a tourist area of the Hua Hin, a resort town on the Gulf of Thailand, three hours drive from Bangkok.

Edwin Wiek, the founder of Wildlife Friends Foundation, which has a centre near Hua Hin, tweeted from the local San Paolo hospital that seven foreigners were injured, one seriously.

A foreign man with a wife and badly injured child had bones sticking out of his legs, according to local people, Mr Wiek tweeted, adding that police stopped him filming the bombsite "as I might tarnish Hua Hin reputation?."

 He described seeing " a lot of blood, towels, tissues, I mean all kinds of stuff that people use to stop the bleeding of the wounded people."

"I saw that on two different sides, about 100 meters away from each other … where tourists are going to have drinks and walk around, two bombs went off that were planted in pot plants," he told the ABC.

"One [was] at an intersection, another one in front of a bar, next to a temple."

Mr Weik said there were no serious injuries in the first blast, but the second bomb caused serious damage.

Hua Hin has dozens of hotels and resorts popular with Western tourists.

It is also the traditional summer retreat for Thailand's King and Queen, who are unwell in Bangkok hospitals.

The bombs exploded ahead of a public holiday on Friday to mark the birthday of Queen Sirikit, which is Thailand's "Mother's Day."

The attack came a day after Thailand's military government warned of threats to the country that has been wracked by years of political upheaval. 

Prime minister Prayuth Chan-ocha, a former army chief, said there are "people who remain dissatisfied with this state of peacefulness, who persist on damaging the country and even our highest institution, all for their own personal gain, through the use of online media and information send from abroad."

Thais voted in a referendum on August 7 on a new constitution that gave supremacy to Thailand's military that seized power in a 2014 coup, as well as the country's traditional elite in Bangkok.

The vote was a severe blow to country's Red Shirt supporters of exiled former prime minister Thaksin Shinawatra.

Only hours before the blasts Mr Prayuth urged Thais to accept the results of the referendum, promising to hold elections in 2017.

"Let us set aside our differences for now and move forward together to confront the complex challenges that lie ahead of us, in making progress, reforming our country, doing away with our conflicts, and reconciling with each other under a new set of rules and regulations," he said.

But the military ignored calls to release politicians are and activists jailed for criticising the referendum. 

Thai authorities have already ordered a tightening of security at the country's tourist venues following the Hua Hin blast. 

Thailand was the target of three bomb attacks last year, the largest a massive explosion placed inside a shrine at the Erawan temple in the centre of Bangkok that killed 20 people and injured 125.

Thai authorities worried about the impact of the blast on the country's tourist insisted the bombing was not a terrorist attack and was carried out by criminals connected to human trafficking.

Tourism accounts for more than 10 percent of Thailand's economy.