A wounded woman is helped after the blast. "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.

Victims await treatment at the hospital. He said they are from the UK, Austria, Italy and Germany. One German woman was aged about 20. Bomb pieces marked as evidence at the scene.

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?." Wildlife Friends Foundation founder Edwin Weik, who arrived at the scene about 10 minutes after the blast, 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.

The Department of Foreign Affairs said Australia's embassy in Bangkok was "in urgent contact with local authorities to determine if any Australians have been affected". However no Australians are believed to have been caught up in the blasts. 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. Tawee Narissirikul, the governor of Prachuap Khiri Khan Province, where the resort town is located, said this sort of attack was a first for Hua Hin. "Now we have to be more cautious about the situation," he said. Anyone concerned for loved ones in Thailand should contact the Department of Foreign Affairs and Trade's 24-hour Consular Emergency Centre on 1300 555 135 within Australia or +61 6261 3305 from overseas.