IRWINDALE (CBSLA) – Authorities are trying to determine why a gunman opened fire on a pedestrian in Irwindale Thursday night, killing him.

The victim, a Hispanic man, was walking along a sidewalk in the 1600 block of West Arrow Highway just before 7 p.m. when a suspect fired shots in his direction, the Los Angeles County Sheriff’s Department reports.

The victim was rushed to a hospital with at least one gunshot wound, where he was pronounced dead. His name was not released.

There is no description of the suspect and no motive, the sheriff’s department said. LASD is assisting Irwindale police with the investigation.