Alex Donaldo Aguilar Vasquez, a 28-year-old Hispanic man, was last seen on September 22, 2008, in San Mateo, California. Born July 28, 1980, he is described as 5 feet 3 inches to 5 feet 4 inches tall, weighing 140 to 150 pounds, with black hair and brown eyes. He may have used the names Fernando Manuel Aguilar Vasquez or Donaldo Aguilar Vasquez.

The last known contact was a phone call to his mother from Reynosa, Tamaulipas, where he said he planned to cross into the United States and would call again once he reached California. He did not have access to a vehicle at the time, and his family has had no contact with him since that call. The San Mateo Police Department lists him as an endangered missing person and his case appears in national missing persons databases.

Very few details about the investigation are available and the case remains unresolved. If anyone knew Alex, his movements in 2008, or has information about his possible crossing from Reynosa, please come forward.