A raid on a South Side home led to the arrest of 36-year-old Julio Cesar Campos and the discovery of 19 assault rifles and 8,000 rounds of ammunition possibly headed to a Mexican drug cartel, San Antonio police said.

Narcotics officers discovered the illegal weapons after conducting a search around 1 a.m. at a home in the 300 block of Stonewall Street.

Narcotics officers had been watching the house for about a week, and said the weapons were being held at the home as part of an international weapons smuggling operation.

San Antonio police also found half an ounce of black tar heroin in the home.

"We're pretty sure they're going to be destined for Mexico to cartels down south. The info we got is weapons are being collected here to be shipped down to Mexico," Sgt. Robert Perez, with the San Antonio Police Narcotics Unit, said.

Weapons seizure

Campos was taken into custody.

San Antonio police say he is a Mexican national and has prior drug convictions. He has been charged with possession with intent to distribute and is also expected to face smuggling charges.

San Antonio police said the group they've been investigating provides weapons to a drug cartel in Mexico. The cartel also sends drugs to the group to be distributed in the U.S.

"As we develop more information, we're sure we're going to have more people arrested down the line," Perez said.

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