Police in Western Australia state Tuesday said one worker died and two others were injured when the roof collapsed on a site where they were working at a university in Perth.

Police Commander Mike Bell told reporters two of the men were on the roof when it gave way, causing them to fall more than 20 meters to the ground. One of those men died at the scene. The third man was inside the building. All three men were in their 20s.

A spokeswoman for a local ambulance service told the Reuters news agency the two survivors were taken to a local hospital, where they were being treated for multiple injuries.

Bell said authorities had not determined what caused the roof to collapse. Local media report Australian authorities are conducting an investigation.