Nogales, Arizona - Two U.S. citizens were arrested after U.S. Border Patrol canines detected four concealed illegal aliens in separate incidents near Amado Saturday.

In the morning, Nogales Station Border Patrol agents discovered two male Mexican nationals hidden inside the trunk of a Nissan Sentra at the Interstate 19 Immigration Checkpoint. Agents arrested the driver, identified as a 54-year-old Tucson woman, for human smuggling. The undocumented aliens, both 30, were arrested and processed for immigration violations.

Hours later, agents at the same immigration checkpoint referred a 33-year-old Douglas man for a secondary inspection after a canine alerted to the Dodge van he was driving. Agents searched the vehicle and discovered two Mexican nationals attempting to hide under the van’s rear seat. Agents arrested the driver for human smuggling. The undocumented aliens were arrested and processed for immigration violations.

Federal law allows agents to charge individuals by complaint, a method that allows the filing of charges for criminal activity without inferring guilt. An individual is presumed innocent unless and until competent evidence is presented to a jury that establishes guilt beyond a reasonable doubt.