The 63 tourists were returning from the Similan Islands when the boat sank, said Lt Col Jakkri Mekamponsuth of the Phang Nga Marine Police.
The speedboat, called Rak Talay Tour, was returning the tourists to Tub Lamu Pier in Tai Muang, on the Phang Nga coast, he added.
“The boat captain called in, saying that they were about 10 nautical miles from the Similans when they struck an object in the water. The hull had cracked and that the vessel had begun taking on water, so he called for help,” Col Jakkri said.
Police and rescue teams were scrambled to render assistance, but a fishing vessel and another tour boat in the area were able to safely recover the tourists, captain and crew, he added.
“No people were injured in the incident,” Col Jakkri said.