Fresno County Sheriff’s detectives arrested four men and seized large amounts of drugs, firearms, and cash during a raid near Justin Garza High School, officials said Friday.

Acting on a tip from Valley Crime Stoppers, detectives investigated reports of illegal drug sales at a property on the 3800 block of N. Grantland Avenue.

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Authorities served a search warrant on Thursday, uncovering about 100 people gathered in and around a shop behind a home.

While most fled the scene, roughly 30 individuals were detained for questioning, according to authorities.

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Investigators discovered the property hosted a recurring event called “Sunday Funday,” where vendors gathered several times a week to sell drugs openly.

The gatherings reportedly began earlier this year, attracting customers of all ages and backgrounds.

Due to the location’s proximity to the high school, detectives believe students may have been aware of the events or made purchases there.

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Officers found four handguns and a range of narcotics, including 400 pounds of processed marijuana, 120 pounds of THC edibles, 60 pounds of concentrated cannabis, 112 ounces of Promethazine syrup, 7 pounds of psilocybin mushrooms, and smaller quantities of other drugs such as cocaine, LSD, and MDMA.