An American tourist was found trapped in a drain in Pattaya on Tuesday night after a passerby heard him calling for help.

Rescuers were called to Soi Thepprasit 8, Bang Lamung district about 7.30pm.

They were directed to a drain on the side of the road. When they looked through the metal grill over the hole, they saw a man about 1.50 metres below, trapped in the 60 centimeter sewer pipe. They opened the grill and lifted him out.

A security guard told police he heard a man yelling, apparently calling out for help. He looked around, but saw no-one. Then he looked down through the grill over the nearby drain, and saw a man below.

Pattaya and tourist police soon arrived at the scene. The trapped man was identified as Jonathan Ioane Vaimaona, 36, an American who arrived in Thailand with his girlfriend on May 12.

Mr Vaimaona appeared exhausted by his ordeal. He was wearing only a pair of pants, his body covered with sludge. Asked how he became stuck in the sewer pipe, his answer was confusing. It was not yet clear what happened.