Ever wonder what makes late-night tacos so addicting?

For one Olivehurst taco truck, the answer is meth (with a side of marijuana).

A three-month undercover sting by the Olivehurst police department, aptly dubbed "Operation Dirty Taco," busted a mobile eatery peddling illegal drugs to its customers.

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Olivehurst police told CBS that the truck was just a shell for a mobile marijuana and methamphetamine operation. Brothers Juan and Ernesto Paez were busted when they sold drugs to undercover agents.

According to the Marysville Appeal-Democrat, the taco truck in question was stocked with over $10,000 in meth, marijuana and drug money.

On Wednesday, agents searched four addresses connected to the taco truck and discovered a larger network of drug trafficking going on behind the scenes, reported SFist.

The Paez brothers are being held at the Yuba County Jail on suspicion of possession of a controlled substance for sale, possession of marijuana for sale, conspiracy and sale of drugs near a school.

To top it all off? The tacos were gross.

“The tacos weren’t that good; they looked to be rather dry and unedible,” said Martin Horan, commander of Yuba-Sutter NET-5 Task Force.

Watch the bust below, courtesy of CBS: