No Malaysian was involved in the twin bombing incident at the popular coastal resort town of Hua Hin late last night which left a Thai woman dead and 20 others including 10 foreign tourists injured.

Hua Hin police station deputy chief Lt Col Samer Yusamran confirmed there were no Malaysians in the casualties' list from the double bombing incidents which occurred several minutes apart at 10pm last night (local time).

"The first bomb went off at 9.59pm, while the second bomb exploded several metres apart, minutes from the first explosion. The bombs were detonated by a mobile phone as the authorities found debris of the phone at the scene of the crime," he told Bernama today.

The deceased Thai woman has been identified as a street food vendor while the foreign tourist casualties' list, he said, included five Italians, three Dutch nationals, an Australian and a German holidaymaker.

Samer said the number of Thais injured in the incident totalled nine, most of whom were street vendors plying their trade at the affected street when the bombs went off, leaving several of them with serious injuries.

All the injured were sent to three nearby medical facilities, Hua Hin General Hospital, San Paolo and Hua Hin Bangkok Hospital, he said.

Most of the foreign tourists suffered light injuries, said Samran.

According to him, the Explosive Ordinance Disposal team had been at the scene sweeping the areas for more evidence to help in their investigation.

"We haven't determined the motive of the incident and we are not ruling out anything. As most of the victims were foreigners, it is a possibility that foreigners were the target of the bombs," he said.

The authorities have tightened security at the resort town which is expecting an influx of tourists taking advantage of the public holidays in Thailand beginning today.

Queen Sirikit's 84th birthday today is a public holiday in Thailand.

The Hua Hin bombing was the second violent incident to hit Thailand yesterday. Another blast occurred earlier in a busy market in Trang, located in the southern part of the country, injuring six people.

One of the injured later died while receiving medical treatment at the nearby hospital.

Prime Minister Gen Prayut Chan-o-cha and his deputy Gen Prawit Wongsuwan, who is also Defence Minister have urged the authorities to hunt down those behind the incident.

Both incidents in Hua Hin and Trang happened just days after Thailand's military-led government successfully conducted a nationwide referendum on Sunday, on the draft constitution.

The referendum which saw 61 percent eligible voters supporting the draft constitution, is part of the government's political roadmap for the return to democracy.