PHILADELPHIA — Police in Philadelphia say a homeless man sleeping in a commercial trash bin has been killed by a trash compactor.

Investigators say the unidentified man was in a North Philadelphia trash bin when a garbage truck picked it up and collected the contents around 4 a.m. Wednesday. The truck's driver activated the compactor a little later.

Police say the driver told officers he thought he heard someone say, "Yo! Yo! Yo!" but did not know where the voice was coming from. He heard the cry again, fainter, at his next stop and alerted authorities.

Emergency personnel declared the man dead at the scene. Police say he wasn't carrying identification but appeared to be in his 40s.

The man's death appears to be an accident and no charges are expected.