Man crushed to death under portable building on worksite

A man has died after being crushed by a portable building on a worksite in the Lower Hunter Valley.

Police were called to equipment hire business Onsite Rental Group on Huntingdale Drive in Thornton about 8:15am today following reports of a workplace incident.

They were unable to save the 55-year-old truck driver who is believed to have been unloading a portable amenities block from a vehicle when it appeared to tip almost wholly onto its side. 

"Initial inquiries indicate the 55 year old male truck driver was unloading a portable amenities block from a truck when he was struck by the load and suffered fatal crush injuries," A SafeWork NSW spokesperson said. 

SafeWork inspectors responded to the site and its investigation is ongoing. 

A report into the incident will be prepared for the coroner.