Officials said the death toll had reached 33, but a private emergency foundation at the scene put it at more than 50. The dead included one Englishwoman, identified as Janet Mawdsley from Newcastle. Mrs Mawdsley's husband John was said by hospital staff to be in serious condition.
Last night, when rescue operations were briefly suspended because of rain, officials estimated that 70 people were still missing in the ruins of the Royal Plaza Hotel in Nakhon Ratchasima, 250 km (150 miles) north- east of Bangkok and off the beaten tourist track. Later two women were brought out alive from the rubble and three more bodies were removed. Nurses at one hospital said one of the dead was a Japanese woman.
'We can still hear voices,' a police rescue worker said as dusk settled over the site and big lights were brought in to aid the rescue workers. They said bottles of oxygen and water had been passed down to isolated groups of survivors.
While the operation was temporarily suspended, officials met to discuss how to proceed. 'There are so many dead bodies we can see, but we are concentrating our efforts on helping the living,' Police Sergeant Suwat Pongsuwan said. An official at a private emergency foundation said more than 50 bodies had been retrieved from the debris of the hotel.
More than 250 teachers and were attending a seminar at the hotel when it collapsed. 'I thought it was an earthquake,' said Malee Sukya, a 36-year- old teacher. 'I saw the window crack and then it broke. I tried to jump out but the building collapsed right away. Everything was black.' Ms Malee, who sustained injuries to her stomach, back and mouth, said the first rescue worker to reach her seemed to be leaving when she shouted: 'I have three children,' and he came back.
The building was a two-storey structure to which four additional storeys had been added, officials said. An additional floor was being put on when the building collapsed. According to local radio reports, the engineer in charge of building the new storey was being detained by police.
'There were people on each floor when it happened and they are now either trapped or buried in debris,' said Pornchai Chitsuwansin, a spokesman for the Ruam Katanyu Foundation, an emergency group. 'The gas smell and the fear of triggering further collapse have slowed rescue workers as they try to do their jobs.'
More than 270 people were injured, officials said, and hospitals issued appeals for blood donations. Mr Pornchai said people being rescued and bodies retrieved at dusk had been on the third floor of the hotel when it collapsed on Friday morning. Those who were on lower floors remain trapped.
'We expect the death toll to rise, definitely past the 100 figure tonight,' Mr Pornchai said. 'There are so many people trapped in what is reduced to a one-and-a-half-storey structure from an original seven-storey building.'
More than 60 employees of the Shell oil company were also attending a meeting in the hotel. Forty others were attending a third meeting.
Channel Nine television reported that 20 foreigners were staying at the 134-room hotel, 10 Americans, seven Japanese, one Swede, one Taiwanese and one Chinese.