A speedboat carrying 36 tourists and crew exploded in flames and thick black smoke near Maiton Island, off Phuket in Thailand.
Fire was seen raging on the vessel, and initial reports said six people suffered injuries.
The speedboat was some 60 yards offshore - and the tourists, mainly from Russia and Kazakhstan, were able to get into the water.
Footage shows the horror in the Andaman Sea.
The Phuket Information Centre said: “The fire spread rapidly. There were 36 crew members and tourists on board.
“Everyone was able to get off the boat in time. However, there were minor injuries from the incident.”
A report said three tourists were injured along with the captain, a guide and the boat’s mechanic.
Later reports said that two were injured with burns and were taken to a waiting ambulance and transferred to hospital.
The Marine Tourist Rescue Centre sent help to the tourists.
The Thai Maritime Enforcement Command Centre and the Royal Thai Navy dispatched the HTMS Hua Hin to assist in the operation.
Maiton Island, also known as Koh Mai Thon, is a small, private island off Phuket’s coast in the Andaman Sea.
It is famed for crystal-clear waters, coral reefs, and soft sandy beaches.
One report said the speedboat had made a swimming stop when the engine exploded and ignited - but for this the casualties could have been far higher.
A report said: “The fire was caused by an engine malfunction.
“While rescue services were getting to the site, the boat washed up on the shore, where it completely burned out.”
