OAKLAND -- A 23-year-old San Leandro man was fatally shot Saturday morning inside a crowded Jack London Square nightclub, police said.

The man's name was not released.

The shooting happened about 1:20 a.m. inside Club Anton, 428 Third St., just east of Broadway.

Police said a party was being held at the club when some kind of disturbance occurred and the man was shot. He was pronounced dead at the scene.

Sgt. Sean Fleming said police are trying to determine whether the man was involved in the disturbance.

Dozens of people were inside the club at the time of the shooting, but there were no other injuries reported.

Fleming said police don't have a motive for what prompted the shooting and that no arrests have been made.

Some people remained at the club and spoke with police about what happened, but he said many others left before officers arrived and that investigators would like to talk to them.

There have been other shootings, including fatal ones, in the Jack London Square area.

On Dec. 8, 2012, a 32-year-old man was fatally shot on the same block as Saturday's shooting. That homicide was solved.

In April 2012, five people, including two 15-year-olds, were shot outside a movie theater on Washington Street. No one died.

On April 25, 2011, two men were shot and killed and others wounded in a street robbery that started outside Sweet Jimmies in the 300 block of Broadway. Those homicides were solved.

Police and Crime Stoppers of Oakland are offering up to $10,000 in reward money for information leading to the arrest of the gunman in Saturday's killing. Anyone with information may call police at 510-238-3821 or a tip line at 510-773-2805.