Man crushed to death under 'crane-like device' in Syd

Two fellow factory workers freed the man, believed to be aged 43, and tried to revive him with CPR.

He had been crushed between two pieces of equipment at a factory in the western Sydney suburb of St Marys about 5.15am (AEST) on Thursday.

A police spokeswoman said it was not yet clear how the man came to be trapped by equipment she described as a "lifting device" often used in factories.

"Whether it has slid or fallen or tilted onto him, we can't say," she told reporters.

An ambulance spokesman said two factory workers were performing CPR on the deceased when paramedics arrived, but the man was pronounced dead at the scene.

Police remain on site and will prepare a report for the coroner.

The matter has been referred to WorkCover.