RIVERSIDE (CBS) — Federal, state and local law enforcement officers raided 40 addresses around Riverside Wednesday, arresting 20 people with ties to a street gang blamed for violence on the city’s eastside, authorities said.

The six-month “Operation Tampa Bay” raid targeted the 1200 Blocc Crips, according to Riverside police Lt. Guy Toussaint. He said the arrests stemmed from drug, weapons and parole violations.

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A total of 36 arrest warrants, 19 state search warrants and 21 probation and parole searches were handled by Riverside police, agents with the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, the California Department of Corrections & Rehabilitation, Corona police, the Riverside County Gang Task Force and other agencies.

According to Toussaint, the 1200 Blocc Crips has been anchored on the eastside for decades. The 147-member, all-black street gang has been involved in deadly assaults, drug trafficking and other crimes.

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Toussaint said the gang has been engaged in a years-long battle for turf with the all-Hispanic Eastside Riva, the city’s oldest gang, as well as the all-Hispanic Casa Blanca gang.

In January 2010, a multi-agency sweep throughout Riverside County dubbed “Operation Promise” targeted the Riva and crips, netting 50 arrests and leading to the seizure of nearly 30 firearms.

Eleven guns were seized during Wednesday’s operation.

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