ANTIOCH (CBS SF) — Police in Oakland and Antioch announced on Thursday the arrests of suspected gang members involved in a feud that authorities say is fueling much of the gun violence plaguing both cities.

The gang sweep was the result of an investigation that began with a probe into the execution-style slaying of 20-year-old Daunzhay Young on the 1800 block of Tioga Pass Way in Antioch on Aug. 29 last year.

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Antioch police said Young, a member of Oakland’s Case Gang, was gunned down by a member of the rival Oakland ENT Gang.

“This initial homicide led to a long-term investigation into the violence surrounding this gang feud,” said Antioch Police Chief Tammany Brooks at a Thursday news conference. “Detectives quickly realized Young’s murder introduced a larger narrative between the ENT and Case criminal street gang rivalry, and this was just the tip of the iceberg.”

Brooks said the investigation led to detectives linking several other gang-related homicides, attempted homicides, and shootings in the months before and after Young’s murder as shootings and reprisal shootings were linked to the gang feud.

During the investigation, dubbed Operation Windstar, detectives with the Oakland and Antioch police departments, along with other Bay Area law enforcement agencies, combined resources to arrest seven people and recover nearly 50 firearms, 15 of which were ghost guns.

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Three men were charged in the Young murder case: Charles Bolden Sr., 42; Charles Bolden Jr., 19; and D’Marco Lindsey, 19. The murder charges against the three include enhancements of lying in wait, making them eligible for life without the possibility of parole or the death sentence, police said.

Two other attempted murders, not associated with the Young murder, were linked to the Case/ENT gang rivalry. On Feb. 27, a man was gunned down in broad daylight with a semiautomatic firearm at an Antioch gas station on Lone Tree Way. On March 9, a targeted, drive-by shooting on Aspen Way in Antioch left two men in critical condition and their vehicle riddled with bullets.

Four men were arrested for the Aspen Way shooting: Trent Allen, 20; Keyshawn McGee, 22; Terryonn Pugh, 20; and Eric Windom, 21. Pugh was also charged in the Lone Tree Way shooting, which led to reprisal shootings in Oakland later that night, police said.

Operation Windstar eventually involved 27 agencies from throughout the state and Nevada, Brooks said. It’s believed the lengthy investigation and arrests will have an effect on reducing violent crime in both cities.

“We believe it’s going to have a significant impact on violent crime the city of Oakland,” said Oakland Police Chief LaRonne Armstrong. “I must also say, that I owe this city an apology that the group in gang violence that started in Oakland has now found itself in the city of Antioch.”

Earlier this week, Armstrong pleaded publicly Monday for an increase in resources for his department following seven new homicides in the past week, including three on Saturday alone. The Oakland City Council voted to fund police programs cut during the pandemic, including Operation Ceasefire, a community-based approach to fighting gun violence in cooperation with police.

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Oakland has seen 41 homicides so far in 2021, compared with 13 homicides at this time last year.