On Wednesday night, members of the Illiana Regional Gang Task Force raided the store near 122nd and Halsted. They arrested one man and seized more than 300 pounds of marijuana inside the store.
Police found a semi-automatic handgun as well as several thousand dollars in drug money. Investigators say the drugs have a street value of nearly a million dollars.
"This was a joint effort, joint investigation that started in the suburbs and led to the city, into the city. Two of our other officers, officer Chris Criska and Juan Zuniga were instrumental in this," said Lt. Maury Richards, Chicago Police Department.
The Illiana task force is made up of Chicago police officers as well as officers from the suburbs and northwest Indiana.
Police say the drugs were found behind a false wall in the basement at the Taste of Mexico on the city's South Side.
Chicago police Comdr. Eric Carter says task force members received information that marijuana was being kept in "multiple rooms" at the store.
Richards says the size of the marijuana seizure indicates the store was part of organized crime operation. Arrested during the raid was 38-year-old Recio Cruz, who was charged with the manufacture and distribution of cannabis.
The Associated Press contributed to this report.