Jeremy Renner was attempting to save his nephew before he was crushed by a 14,000lb snow plough – leaving him with 30 broken bones.
New details from the horror accident reveal that the Marvel actor, 52, was trying to stop his Pistunbully snowcat from hitting his nephew on New Year's Day in Nevada.
Reports say the vehicle's parking brake, which could have prevented the horror ordeal, was not engaged - causing it to slide sideways, rolling over Jeremy's body.
According to a redacted Nevada sheriff's office incident report, Jeremy had been using the vehicle to free his relative's truck out of the snow before the terrifying incident.
After rolling over Jeremy, leaving behind horrific injuries, it continued down onto the road.
"The Pistenbully snow groomer began sliding causing Renner to exit the vehicle without setting the emergency brake," the report reads, per CNN who obtained it.
It continued: "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."
The outlet reports "mechanical issues may have been a factor in this accident", noting that a brake light indicating - telling the driver information on the brake - was not working.
Details from the incident report reveal Jeremy had attempted to jump onto the vehicle's moving track to stop it sliding - he was then "immediately pulled under the left side track".
Following the scary accident, Jeremy has since taken to Twitter to share an update on his condition, sharing a picture of himself lying on a hospital bed.
He wrote: "I want to thank EVERYONE for their messages and thoughtfulness. 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."
A 911 call from the scene of Jeremy's horror accident recently revealed he was crying out in pain, with his neighbour saying he had been "crushed" by a snow plough on New Year's Day.
In newly released audio, Jeremy can be heard moaning in pain in the background of the desperate emergency call, as the neighbour explained his injuries, including damage to his ribs, chest and head.
The unidentified neighbour said Jeremy lost "a lot of blood" in the accident. He was told to "lay still" while the emergency operator asked the neighbour questions.
Jeremy was later airlifted to hospital from a private road. He was said to be in a critical but stable condition after undergoing surgery.
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