Patrol Agent Jose P. Gamez, Jr. was working the 4:00 p.m. to 12 midnight shift in the area of an isolated checkgate on the Maverick County Irrigation Canal in the Quemado Valley, 25 miles north of Eagle Pass, Texas. Patrol Agent Frank J. Lugo, with whom Gamez was working, reported him missing late on April 21, 1978. According to Agent Lugo, he had become separated from Gamez while they were attempting to apprehend four or five undocumented aliens.
Agent Gamez's body was recovered from the canal the next morning and it was presumed he had fallen into the canal and drowned. A few days later, the Bexar County Medical Examiner's report revealed Agent Gamez had been choked, probably with a board, and dragged to the canal by an assailant or assailants unknown. He was deceased when he was thrown into the water.