A mechanic was injured on Monday morning when a speedboat he was manning caught fire near a beach in Phangnga's Takua Thung district, local officials said.
The incident was reported at 10.30am at Ao Man in Ban Yansaba aboard a two-engine speedboat, the BBC Sealion 9, which had brought 20 foreign tourists from Phuket to the beach.
None of the tourists were injured in the incident.
Local officials led by Sayan Kijmano, chief of the provincial disaster prevention and mitigation office, and Pramote Kaewnam, assistant chief of Ao Phangnga National Park, went to inspect the boat.
Wanchart Ounkhao, the boat's skipper, told officials that the vessel left Laem Sai Pier in Phuket for Ao Man with 20 tourists from the Middle East, but they were already on the beach when the fire broke out.
According to Mr Wanchart, while the tourists were enjoying their time on the beach, there was a loud explosion from the boat and it erupted into flames. The fire engulfed the entire vessel.
He said the mechanic, identified as Sunkinlee Promchai, who was manning the boat was injured in the incident. He was helped out by witnesses and rushed to Takua Thung Hospital before being transferred to Thalang Hospital in Phuket.
According to local officials, another speedboat was dispatched to take the shocked but unharmed tourists back to Phuket.
Natchapong Pranit, a marine official in Phangnga, said on Monday a team was investigating the cause of the fire and legal action would be taken against people responsible if any wrongdoing is found.