At about 7 p.m. Saturday, police officers were sent to the Gray's Meadow apartment complex on Meadow Way just east of U.S. Highway 101 in southern Santa Rosa after receiving a report of a fight involving about 10 people.
Responding officers found a 16-year-old Santa Rosa boy bleeding from cuts on his head and face sustained after he was struck over the head with a gun during the commotion.
One man was arrested that night on suspicion of assault with gang-related enhancements, but the investigation was ongoing.
Detectives from the Santa Rosa and Fairfield police gang units served the search warrant Monday at an apartment in the 600 block of East Travis Boulevard in Fairfield, where they arrested a juvenile with ties to Santa Rosa.
A search of the apartment complex yielded a firearm police believe was used in Saturday's fight. Police arrested the Fairfield boy on suspicion of being an accessory to a crime, possession of a concealed handgun and gang-related enhancements.
The boy was booked into Sonoma County Juvenile Justice Center for those violations.
Witnesses to Saturday night's fight told police that a group of young men and women who had gathered in the complex's common area had become engaged in a fight.
People associated with the Norteno street gang reportedly shouted gang-related epithets during the fight, police said, and 23-year-old Nicholas Cacace allegedly pulled a handgun from his waistband and pointed it at the crowd.
Cacace then shouted at the crowd, and allegedly struck the 16-year-old Santa Rosa boy in the head with the gun, causing his injuries, police said.
Police later arrested Cacace on suspicion of assault with a deadly weapon, and investigations indicated that he has ties to the Nortenos.
Detectives are still investigating this incident, and witnesses or anyone with information about the incident should contact investigators at (707) 543-3697.