Inadequate shoring may have caused the roof collapse yesterday in Houston that injured nine construction workers at a hotel being built in north Houston.

According to news sources, the incident occurred while workers were pouring concrete. A Houston Public Works (HPW) inspector dispatched to the scene felt the temporary support system in place while the concrete was being poured was "inadequate," said HPW spokesperson Erin Jones, a spokesperson with Houston Public Works, said.

Jones said the project has undergone several inspections, including two related to concrete.

None of the injuries were deemed life threatening.

The general contractor on the site is Classic Construction.