Two U.S. citizens were arrested Sunday after approximately $10,000 worth of black tar heroin was discovered in the woman's bra, U.S. Border Patrol officials said.

Agents released images Wednesday showing the package discovered as well as an image of the driver with her face concealed.

The package weighed a little over a pound and had an estimated street value of $10,170, agents said.

The woman was driving a Nissan Altima through the checkpoint on Highway 86 near Salton City, California at approximately 8:30 a.m. on Sunday, Dec. 23.

Agents said a canine team alerted to the vehicle so they sent the car over to secondary inspection.

Once there, agents said they found a package hidden in the driver's bra.

Agents said the package contained something consistent with the characteristics of black tar heroin.

The woman, a 45-year-old U.S. citizen, and her male passenger, identified only as a 29-year-old U.S. citizen, were taken into custody by the Border Crime Suppression Team to face charges of smuggling heroin.