Around 20 missing in boat capsize off Thailand's Phuket

Around 20 people are missing after a diving boat capsized in rough seas off the Thai tourist island of Phuket, an official at the Department of Disaster Prevention and Mitigation said late today.

The boat was carrying 90 passengers when it capsized "half of them were rescued, the operation is still ongoing," an official at the department, which is based in Bangkok told AFP, requesting not to be named.

The boat was returning to Phuket from Koh Racha.

Footage shared on Facebook showed officials at a pier gathering information as the rescue operation unfolded in darkness behind them.

It was not immediately clear if the passengers were tourists, but the area is a magnet for overseas visitors.

In a separate incident in the same area this evening a yacht called the Senerita carrying 39 people also capsized, the official added.

An initial report said all of the passengers were pulled from the sea alive but the official who spoke to AFP could not provide any further information.

Thailand is already in the global spotlight for a dramatic rescue mission in the north of the country, after 12 boys and their football coach were trapped in a cave complex.