BERLIN (Reuters) - A 65-year-old man thought to be sleeping while sitting upright on a Berlin underground train as it cross-crossed the German capital was actually dead, police said on Sunday.

"It's tragic," a Berlin police spokeswoman said. "We don't know how long he was sitting dead on the train nor do we know the exact cause of death yet. There are no indications of foul play. He seems to have died of natural causes."

 Not the real man.

The man was found in the U-8 underground train line that runs all night at the Weinmeisterstrasse station at 5:45 a.m. when a rail worker tried wake the man up by gently shaking him. Medics were called in but could only pronounce the man dead.

A preliminary investigation showed no indications of the man being murdered. A more detailed autopsy is planned for Monday.