The casino was being operated in the area of North Capitol Avenue and Avenue B. SJPD says gambling and other illegal activity were taking place, including drug dealing, and a stolen property marketplace.
On Oct. 13, SJPD obtained search and arrest warrants and arrested seven of the operators of the casino.
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Police were able to link a stabbing to one of the operators and five of the seven arrested had outstanding warrants for their arrest.
One operator had a loaded gun and cocaine on him when arrested, and more cocaine, drug paraphernalia, money, and casino machines were found.
Anyone with information about the underground casino or any similar operations can contact SJPD's Burglary Prevention Unit at (408) 537-1200.