OSAKA -- Police found a man with a serious head injury lying on a street in the city of Higashi-Osaka early Thursday after receiving an emergency call from a neighbor who said he noticed him after hearing something hit the ground.

The man, identified as 42-year-old Shoji Azeura, unemployed, was admitted to a nearby hospital but died.

Azeura, a resident of Higashi-Osaka, was found lying in front of a five-story building after police received the emergency call at around 6:05 a.m., investigators said.

Witnesses said Azeura had been drinking by himself at a bar on the fourth floor of the building.

Eight people who were in the bar at the time, including the manager, told police that Azeura got into a quarrel with the manager after claiming he couldn't pay his bill and left.

Azeura is believed to have fallen from a stairwell landing on the fourth floor, but no one actually saw him fall.

Police are trying to determine whether he fell by accident or was a crime victim. An autopsy is to be conducted to determine the cause of death.