A four-storey building in Bangkok's Soi Ramkhamhaeng 5 1/2 area, which was in the process of being demolished, partially collapsed on Monday afternoon, resulting in injuries to two passers-by.
Sopita Thongkerd, 23, and Napaporn Seiboonreung, 54, had been hit by falling debris but were safe, said Pol Major Sasipan Khong-eard of Hua Mark police station.
Bang Kapi District Office has now suspended the building's demolition work indefinitely, pending a safety investigation.
Following the 1.25pm collapse, police and rescue workers quickly sealed the scene to make way for a search for any other people that may have been trapped amid the debris, while police and volunteers directed traffic flows away from the congested area in front of the building on Ramkhamhaeng Road.
Police suspect that the collapse of the building, which used to be an old cinema, might have resulted from the ongoing demolition work.
Bang Kapi public works official Thawatchai Thawitiyakul said the collapse had taken place while the contractor's nine workers were demolishing the building, resulting in tremors that caused some parts of the third floor to crash onto the second floor's balcony.
Initial examination of the site found that the workers had placed more than three-metre-high tin sheets to cover the area, as required under the building-demolition standard, he said.
The cause of the collapse would be officially established after further inspection of the building structure and consideration of related factors, the official added.