The paper was so heavy that getting it off Jefferson Troester's body took several hours, WCAU-TV reported.
Troester and a conductor were operating a six-car Upper Merion & Plymouth Railroad train that arrived at Philadelphia Newspapers' Upper Merion plant shortly after 9 a.m., The Philadelphia Inquirer reported. Each car held 70 rolls of newsprint, each about 4 feet by 4 feet and weighing around 1,800 pounds.
Two of the rolls slid out when Troester opened the door, police said, and one landed on his chest.
"It was an unfortunate, freak accident," Upper Merion Police Lt. Thomas Nolan told WCAU.
The plant is owned by the company that publishes the Inquirer and the Philadelphia Daily News. The Upper Merion & Plymouth is a short-haul freight line.
Mark Block, a spokesman for the newspaper company, said Troester and his colleague were alone on the loading dock at the time of the accident. He said the Occupational Safety and Health Administration and Federal Railway Administration will investigate the death.
Troester, 43, lived in Claymont, Del.
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