Mexico's federal police arrested a pair of U.S. citizens after finding more than two tons of marijuana in their vehicle in the northwestern state of Sinaloa, officials said.

The suspects were riding on the Mexico City-Nogales highway when they got into an accident between the town of Los Mochis and the border with the neighboring state of Sonora.

The federal police requested the assistance of medical personnel and then discovered a secret compartment in the roof where 962 packets containing more than two tons of marijuana had been stashed.

The driver of the white Ford motorhome was identified as 38-year-old Eric Michael Kubek while the other passenger was 46-year-old Rhonda Marie Glick.

Both identified themselves as U.S. citizens who live in San Diego, California.

After they received medical treatment, the two were taken into custody and the U.S. consulate in the Sonoran city of Hermosillo was notified of the arrests.