A 32-year-old Nigerian man was found shot to death in an apartment building in Asaka, Saitama Prefecture, on Thursday morning, police said.
A resident discovered the body of Ugboaja Billy Ugochukwu near a first-floor stairway in the Heights Koma apartment complex at around 6:30 a.m.
He had a bullet wound in the left side of his chest.
One neighbor reported hearing a gunshot at around 2 a.m. and the sound of a car speeding away from the scene immediately afterward.
Police have detected no evidence of a struggle between the victim and his assailant at the apartment, and more than 100,000 yen was left inside the victim's wallet.
The owner of the building, located 1.5 km northwest of Asaka Station on the Tobu-Tojo Line, said the Nigerian moved into the building around six months ago.
He ran a store selling imported clothing in Tokyo's Ikebukuro Ward.
Ugochukwu's Japanese wife, who lives in Tokyo's Toshima Ward, was quoted by police as saying she received a call from her husband at around 2:15 a.m., and that he said he was returning to the apartment in Asaka.