SALTON CITY, Calif. – Officers with the United States Customs and Border Protection said Friday that they discovered liquid meth inside the gas tank of a vehicle stopped at an immigration checkpoint in Salton City.

The arrest happened around 5:20 a.m. on July 1 when officers pulled over a 2003 Chevrolet Silverado at a checkpoint on State Route 86. The vehicle was referred to the secondary inspection zone where a Border Patrol K-9 alerted officers to the possible presence of narcotics.

During the secondary inspection, officers searched the gas cap which looked to have been tampered with, according to CBP. While using a portable video scope to inspect the gas tank, officers discovered a liquid on the instrument that began to harden and turn white upon its removal from the tank. The liquid was tested and came back positive for methamphetamines.

The exact amount of methamphetamines discovered is unknown due to the drug’s liquid form.

Officers say that the driver, a permanent legal resident of the United States, along with the vehicle and narcotics were handed over to the Drug Enforcement Agency.