The man was killed instantly when he was hit by an articulated truck at around 4am on Wednesday. He had been lying down on a four-lane main road.
"The 45-year-old driver of the truck could not react in time, despite braking immediately, and rolled over the 25-year-old lying on a pedestrian crossing," police said in a statement.
He became caught on the twinned wheel of the vehicle and was carried 25 metres down the road near the central German town of Bad Oeynhausen in North Rhine-Westphalia.
Police said they were searching for a second truck driver who had previously spotted the man but managed to avoid him. They hope the driver may be able to help explain why the man was there.
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