An autopsy was conducted yesterday on the body of a 21-year-old man found at the bottom of a staircase outside a city apartment house where he lived, police said.

Todd Rasner was found outside 50 Union Street when a maintenance man came to the building at 10:30 a.m. Sunday, police said.

Police said the cause of death has not yet been determined but Rasner may have fallen down the steps. There were no signs of foul play.