Arrested were the 38-year-old suspected local kingpin of the drug ring, a Mexican national in the U.S. illegally, along with two other men at the scene. A woman at the house was questioned and released.
The arrested suspects were being held without bail Thursday at the Salt Lake County Jail on suspicion of drug possession and distribution counts.
Bell said detectives were certain the operation was connected to one of the Mexican drug cartels, but they had not identified which one.
However, the drugs were believed to have been smuggled across the border from Nogales, where the infamous Sinaloa cartel has held sway. The drugs ended up in Stockton, Calif., before being taken to the Salt Lake Valley, police say.
Bell said it was apparent that the hidden compartments — some involving combination lock-like releases and hydraulic mechanisms located under seats, floorboards and instrument panels — were the kind of professional expertise typical of well-funded, major Mexican drug operations.
While no more arrests were anticipated in Utah as part of this investigation, Bell said it was likely other law enforcement agencies could use information developed from the raids to put pressure on the cartel's operations in California and Mexico.
Meanwhile, the seizures of such a large amount of narcotics should put a dent in the local traffic for the drug, which would have provided substantial illicit sales once the pure heroin was "stepped on," or cut by dealers, Bell said.
"This should impact the market here at least for a short while. That's a significant amount of heroin to take off the streets," he said.