Authorities say the roof of a privately run East Texas prison has collapsed, temporarily trapping dozens of inmates and injuring 20 – 10 of whom went to nearby hospitals.

A Texas prison system spokesman, Jason Clark, says wallboard fell from the ceiling of a housing area. It happened midday Saturday at the Diboll Correctional Centre about 100 miles north-east of Houston.

Warden David Driskell says 84 inmates were in the area and many were trapped briefly. Sgt Brandan Lovell of Diboll police says 20 inmates were injured, with 10 taken to hospitals. Driskell said the others were treated at the scene for minor injuries, none of which appeared life-threatening.

Prison officials were trying to determine what caused the collapse.

The 518-bed minimum-security facility is operated by Management & Training Corp,, based in Centerville, Utah.