Nine out of the 10 gunmen, who seized a provincial Thai hospital on Monday, were killed by Thai forces Tuesday, thus bringing to an end the 24-hour hostage drama, Thai officials said.

Some 400 hostages trapped in the hospital in the western province of Rachaburi are all safe and have left the hospital, the Independent Television reported.

The army and police have confirmed that one gunman was missing in the action while two Thai policemen were slightly injured.

Thailand is pursuing the missing gunman and has vowed to bring him to justice if he is arrested.

Thai military and police forces stormed the hospital taken over Monday by the 10 gunmen, believed to be from a Myanmar ethnic Karen guerrilla splinter group called "God's Army," early Tuesday morning.

It is still not clear how many Thai servicemen had taken part in the assault, but witnesses saw trucks and jeeps filled with policemen and soldiers speeding into the hospital before the action.

Thai government spokesman Akapol Sorasuchart confirmed the successful assault, saying the government had worked out the plan of action Monday night.

The government had agreed to consider the demands by the gunmen to buy time for the preparation of the action, he said.

Near midnight Monday, Thai Prime Minister Chuan Leekpai and Supreme Commander Mongkon Ampornpisit went to Rachaburi Province, bordering Myanmar, to direct the negotiation and the assault.

Thailand had earlier condemned the seizure of the hospital as an "international terrorist act," which is against Thai and international laws and violates the sovereignty of the kingdom. (Xinhua)