Police responded to the shooting at Yankee Doodles sports bar and restaurant at about 2 a.m. and found 36-year-old Michael Martoni shot in the upper torso. He died at the scene.
Police say they don't know if the two men knew each other.
Belmont Shore is an upscale beach community with shops and restaurants in Long Beach and regarded as one of the safest areas in Long Beach.
Anyone with information is urged to call the Long Beach Police Department at (562) 570-7244.
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