This is the heroic moment kindhearted divers released lost dolphins back into the sea during a liveaboard trip.

Five underwater explorers rescued the mother dolphin and her calf that had become stranded in shallow waters near the Asia Marina Pier at Si-Re Island in Phuket, Thailand.

Footage shows Kan, Pouem, Natthawut, Teesophon, and Phorrapatra aboard a rubber boat carefully lifting the sea creatures and placing them into tubs filled with water on the morning of October 27.

They then manoeuvred out of the area and headed towards the open sea.

Once offshore, the group gently carried the mammals and released them into the water, where they swam away.

Phorrapatra said: 'The mother and calf were swimming at the surface, appearing weak and unable to find their way back to deeper water.

'They approached our small boat as we were returning from transporting divers to shore, allowing us to guide them on board so we could release them back into deeper water.'

The Phuket Marine Biological Centre reported that around 60 cetaceans, including dolphins and small whales, become stranded along Phuket's coasts each year, often due to illness, injury, or disorientation in shallow waters.