A Border Patrol dog alerted to a vehicle at the Arizona 90 checkpoint on Aug. 31, 2017. Agents found two Mexican nationals being smuggled inside. The two occupants of the car were arrested for human smuggling.

Customs and Border Protection

Two Tucson residents were arrested after Border Patrol agents found two undocumented immigrants hiding in the trunk of their car Thursday near Whetstone.

Agents working at the Arizona 90 checkpoint sent a 2008 Infiniti coupe for a secondary inspection after an agency dog alerted to the vehicle. In the trunk, agents found two adult males from Mexico hiding in the trunk, according to a news release from the Customs and Border Protection.

The car's driver, 24, and passenger, 26, both from Tucson, were arrested on suspicion of human smuggling. The two Mexican nationals were being held on immigration violations.

The tactic of concealing humans in the trunks of vehicles is commonly used by smugglers, but it puts those in the trunk in great personal danger, including suffocation, heat stroke or injury from a collision, the CBP said.