Police will charge contractors of the building that collapsed on Monday in Pathum Thani province for negligence causing deaths and injuries.
Until now, at least three people, including a mother and her baby, were killed.
Pol Maj Gen Smithi Mukdasanit, provincial police commander said that police now learnt about the names of the contractors of the building and prepared to charge them with negligence that caused deaths and wounded.
Their licenses would be inspected if they were valid or not.
Meanwhile Chayan Sirimart, provincial disaster prevention and migitation said the mother who was killed in the accident was identified only as Oun while the third victim was Chettha Kampuchat.
He also referred to Klanarong Prabpai, 24, who has been trapped under the debris since yesterday, saying the rescue works on him had to be very careful to prevent more collapsing.
The 19 injured workers were now receiving treatment at hospitals in the area, he added.