Sergio Alberto Lopez Montoya was 23 when he was last seen on August 6, 2015, as he attempted to cross from Mexico toward the United States. His route was believed to take him near Lukeville, Arizona, close to State Route 86. No contact or confirmed sightings have been reported since that day.

At the time he disappeared Sergio was described as a Hispanic male, 5 feet 2 to 5 feet 3 inches tall, 150 to 160 pounds, with brown hair and brown eyes. Distinctive marks included a previously broken right wrist, a small scar on his torso, and a belt with a bull or longhorn design when last seen. The Phoenix Police Department recorded the investigation on October 17, 2020.

If anyone knew Sergio, saw him in southern Arizona in August 2015, or has information about his movements near Lukeville or State Route 86, please come forward.