A 22-year-old student was bench-pressing 315 pounds (143kg) when the barbell slipped from his hands and crushed him to death in a US gym.

Kyle Thomson, a senior in the College of Liberal Arts and Sciences at Iowa State University in the city of Ames, was working out at Elite Edge Transformation Centre in Ankeny, north of Des Moines.

Ankeny Fire Department chief James Clack said the barbell fell on Thomson’s neck after it slipped from his hands.

He was taken to a Des Moines hospital, where he was pronounced dead.

A spokesman for the gym said Thomson was lifting as part of an advanced baseball training program. He was with a spotter at the time of the incident.

A former co-worker Stephen Smith told Des Moines Register that Thomson was passionate about lifting weights.

Thomson posted on Facebook in October that he had completed the gym’s ‘20-pound challenge’, which meant he had shed 9kg in six weeks.

Thomson, who would have graduated in May next year, wanted to work for Des Moines Police Department as a dog handler.

His funeral will be held on Saturday (local time).

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