One man died and another was wounded following a shooting at Pioneer Park in San Dimas on Sunday afternoon, authorities said.
The fatal gunfire was first reported about 6:20 p.m. at the park along the 200 block of Acacia Street.
"One victim was pronounced dead at the scene and the other was transported to a local hospital for treatment," Deputy Tracy Koerner of the Los Angeles County Sheriff's Department Information Bureau said in a written statement.
Sheriff's officials described both victims only as men.
A relative of the man killed in the shooting told KTLA he was a 33-year-old San Dimas resident.
No further details were available as the investigation remained in its early stages.
Anyone with information was asked to call the Sheriff's Homicide Bureau at 323-890-5500. Tips may also be submitted anonymously to L.A. Regional Crime Stoppers at 800-222-8477.