Media playback is unsupported on your device Media caption Local police confirmed that the car used in the attack had been stolen

Seven people have suffered minor injuries on the popular tourist island of Koh Samui in Thailand after a vehicle exploded, local media say.

The explosion happened at about 23:30 local time (16:30 GMT) in the Central Festival shopping mall.

Six Thais and a 12-year-old Italian girl suffered injuries.

Local officials believe the vehicle may have been brought to Koh Samui from one of three southern Thai provinces where Islamist militants operate.

However, officials say the exact provenance of the vehicle has yet to be established.

"The authorities are still investigating the scene to find out more details before linking it to any insurgency groups,'' said the island's disaster prevention chief Poonsak Sophonpathumrak told the Associated Press.

There were reports of other fires starting nearby at a shopping centre and convenience shop at the same time as the explosion.

The Samui Times said those injured have been treated for shrapnel wounds and shock.

Poonsak Sophonpathumrak said the bomb went off after a fashion show in the basement of the mall near the popular Chaweng beach.

He said a number of vehicles had been damaged.

Koh Samui is in Surat Thani province, further north from the three provinces which have seen repeated Islamist violence since 2004.

More than 5,000 people have been killed since the Islamic insurgency began, seeking more autonomy for the ethnically-Malay region.

Prime Minister Prayuth Chan-ocha ordered security in the capital, Bangkok, to be ramped up in February after two bomb blasts outside a luxury shopping centre injured one person.

Koh Samui, one of the country's top island destinations for tourists, has not been a target of militant attacks in the past.