Jeremy Renner was trying to save nephew from being hit when he was crushed, sheriff's report says

Avengers star Jeremy Renner was trying to stop his snow-plough from hitting his nephew when he was pulled underneath and seriously injured.

Renner, who turned 52 while in ICU, was airlifted to hospital after he was hit by his own vehicle outside his home near Lake Tahoe in the Sierra Nevada mountains on New Year's Day.

New details about the incident have emerged with the release of Washoe County Sheriff’s Office report, which states that Renner was attempting to free his adult nephew’s truck from the snow at the time.

The report, seen by CNN, says the parking brake wasn’t engaged as the snow-removal tractor started to slide. The brake’s indicator light inside the cab had not been working and the report claimed ‘mechanical issues may have been a factor in this accident’.

It reads: “The PistenBully snow groomer began sliding causing Renner to exit the vehicle without setting the emergency brake.

@jeremyrenner/Instagram

“Although the PistenBully had some mechanical issues, it is believed based on our mechanical inspection that the parking brake would keep the Pistenbully from moving forward. When Renner attempted to stop or divert the Pistenbully to avoid injury to (his nephew), he was pulled under the vehicle by the track and run over.”

In a press conference shortly after the accident, Washoe County Sheriff Darin Balaam said the actor had been 'run over' by an 'extremely large piece of snow-removal equipment' weighing 'at least 14,330 pounds', adding that the actor's PistenBully became stuck.

"He went to retrieve his PistenBully or SnowCat – an extremely large piece of snow-moving equipment – to get his vehicle moving," Balaam said.

@jeremyrenner/Instagram

"After moving the vehicle from the stuck location Mr Renner got out of the PistenBully to speak to his family member and it started to roll.

"He attempted to try and get into the driver’s seat of the PistenBully. It was at this point that he was run over by the PistenBully."

Since being hospitalised, Renner has shared regular updates on social media and has thanked his fans for their support and well-wishes.

He was released from hospital over the weekend and will continue his recovery at home, where he revealed he’d broken more than 30 bones in the accident.

@jeremyrenner/Instagram

In a post on Saturday January 21, he wrote: "Morning workouts, resolutions all changed this particular new years….

"Spawned from tragedy for my entire family, and quickly focused into uniting actionable love.

"I want to thank EVERYONE for their messages and thoughtfulness for my family and I ….

"Much love and appreciation to you all.

"These 30 plus broken bones will mend , grow stronger, just like the love and bond with family and friends deepens.

"Love and blessings to you all."