At least 839 people were killed and more than 7,200 injured by the tsunami on Sunday morning in southern Thailand, the Thai Interior Ministry said Monday.

Earlier in the day, Thai Prime Minister Thaksin Shinawatra said around 700 people were killed by tidal waves.

Between 600 to 700 people were killed by strong waves hitting the country's southwest coast area, the prime minister said after an emergency meeting held in the heavily-hit resort island of Phuket.

"I have asked the army to prepare 1,000 body bags," he told reporters.

Thaksin, however, didn't give specific casualties caused by thetsunami triggered out by an earthquake in the sea close to northeastern Indonesia on Sunday morning.

Local media also quoted rescue workers as saying that around 300 people probably died in the isolated resort island of Phi Phi.

The Thai navy has sent warships and helicopters to rescue people trapped on the island and searched for those reportedly missing.

Many of the dead and missing were foreign tourists spending their Christmas vacation in Thailand's southwestern coast that is famous for idyllic scenery.