Two men are behind bars in connection with a drug bust involving a dozen law enforcement agencies that resulted in the seizure of $8.4 million in cocaine, the Orange County Sheriff’s Department announced Friday.

The men, ages 24 and 38, were arrested after investigators with the 12-agency operation made a traffic stop on the 60 Freeway about 8 p.m. Thursday and found a “substantial” amount of drugs in the older-model Nissan Versa, according to Orange County sheriff’s officials.

Investigators obtained a search warrant for the suspects’ home in the Inland Empire, where they discovered a backyard bunker stacked with cocaine, sheriff’s officials said. The street value of the 308 pounds of cocaine seized from the car and the bunker was about $8.4 million, officials said.

Sheriff’s spokeswoman Jaimee Blashaw declined to identify the suspects or their city of residence, saying the release of the information could hinder the ongoing investigation.

The agencies involved in the operation, along with the Orange County sheriff, include the FBI, U.S. Drug Enforcement Administration, Cal State Fullerton police, and the Orange, Buena Park, Tustin, Newport Beach, Fullerton, Huntington Beach, Santa Ana, Fullerton and Ontario police departments.