Warning: Graphic
A US soldier has been hailed a hero after he had to sever his own leg to save his crewmates.
Ezra Maes, 21, was asleep in a tank as part of an overnight military training exercise in Poland last year when he was woken up by the machine rolling downhill.
"I called out to the driver, 'Step on the brakes'," he said.
"But he shouted back that it wasn't him."
The crew tried to stop the tank but nothing was working and the machine continued to roll down the hill at nearly 145km/h.
"We realised there was nothing else we could do and just held on," he recalled.
The tank ended up crashing into an embankment, sending Maes flying across it. His leg got caught in a gear and he was hurt.
Stuck under the machinery, he worried for the safety of the rest of his crew so was determined to free himself.
"I pushed and pulled at my leg as hard as I could to get loose and felt a sharp tear," he said.
"I thought I had dislodged my leg, but when I moved away, my leg was completely gone."
Bleeding profusely, he rushed to the tank and grabbed a tourniquet from the medical kit.
"All I could think about was no one knows we're down here," he said.
"Either I step up or we all die."
He managed to stop his bleeding and called out to another soldier, Sergeant Aechere Crump, and threw his phone to him.
He unlocked the phone and texted a friend to get help for the crew.
Maes was rushed to the hospital before being flown to Landstuhl Regional Medical Centre in Germany.
He is now getting treatment at the at the Brooke Army Medical Centre Warrior Transition Battalion in Houston, Texas.
Doctors could not save his leg.
He says he feels lucky to have survived.
"I feel super lucky. My crew all does. So many things could have gone wrong," he said.
"Besides my leg, we all walked away pretty much unscathed."