Frederick Manuel Aragon, 28, was last seen at his Vacaville, California, home on July 18, 1987. He was wearing a red-checkered long-sleeved shirt and jeans that day. Frederick had a behavior disorder, wore eyeglasses, and had two missing front teeth replaced with false teeth.

At disappearance he was driving a red 1973 Datsun pickup truck. That vehicle was recovered on February 2, 1988, abandoned near the entrance to the Presidio Army Base in San Francisco, but no other trace of Frederick was ever found. The circumstances are described as suspicious and the case has attracted few leads since.

The Vacaville Police Department remains the primary investigating agency and the family continues to seek answers. If anyone knew Frederick, saw his truck, or has information about his movements in July 1987, please come forward.