A hospital under construction just east of Bangkok's main airport collapsed on Tuesday, killing at least 11 people and injuring 16, police said.
"The building collapsed, killing 11 construction workers," said Korawat Hanpradit, superintendent of Bang Phli police station in Samut Prakarn province.
Some of the injured were in critical condition, hospital sources said.
Emergency workers were checking for survivors who may still be trapped under the rubble at the construction site 20 km (12 miles) from Bangkok's Suvarnabhumi airport.
Rights groups have criticised Thailand's lax worker safety records, particularly in regard to migrants from neighbouring Laos, Cambodia and Myanmar, who make up around five percent of the country's workforce.
Many of them toil in low-paying jobs in factories, construction sites and on rickety fishing boats.