A Taiwanese court on late Tuesday approved the detention of three people involved in constructing an apartment building that collapsed in a deadly earthquake at the weekend.

Lin Ming-hui, the former owner of the defunct Weiguan real estate company, and two associates are being held on suspicion of negligent homicide due to “obvious defects” in the use of steel in the construction and questions over supervision, Tainan District Court said in an e-mailed statement. At least 45 people died and nearly 100 others are still missing, according to the National Fire Agency.

“The court approved a request for detention on suspicion of negligent homicide and concerns over collusion,” court spokeswoman Kuo Jenshiow said by phone. The executives will be detained for two months while prosecutors continue their investigation.

More than 530 people were injured when nine buildings buckled during the 6.4-magnitude quake in the island’s southwest early Saturday. A 10-day-old baby girl was among the dead. Rescue workers started using heavy machinery Tuesday to dig through the rubble of the collapsed 17-story residential tower built by Weiguan in the city of Tainan.

Rescuers have detected signs of life from a person, likely a man, who has been trapped for nearly 100 hours, and are digging through collapsed walls and pillars to get to him, the city government said Wednesday.

Taiwan is prone to quakes because it’s near the convergence of two tectonic plates — the Philippine Sea Plate and Eurasia Plate. There have been about 79 quakes greater than 4.5 in the area since the beginning of last year, according to the U.S. Geological Survey.

The epicenter of Saturday’s temblor was in Kaohsiung, about 300 kilometers (185 miles) southwest of Taipei, at a depth of 16.7 kilometers, according to the Central Weather Bureau website. There were at least 40 aftershocks.