Authorities say an 18-year-old has admitted to his involvement in the fatal drive-by shooting of a Mission man late last week as investigators search for three other suspects.

David Robles was identified as one of four suspects accused in the shooting death of 34-year-old Jessie Rey Saenz of Mission, according to a news release from the Hidalgo County Sheriff’s Office.

On May 5, deputies with the sheriff’s office were dispatched to the 1800 block of Chicago Street in rural Alton in reference to a drive-by shooting, where they found Saenz on the side of the road with multiple gunshot wounds.

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Hidalgo County Sheriff Eddie Guerra previously said the shooting is believed to be drug-related.

“Witnesses identified the suspect vehicle as a white truck and stated that individuals inside the residence returned fire, striking the suspect vehicle as it fled,” the release stated.

A witness stated that a white Chevy Silverado that was owned by Robles’ half-brother - Reynaldo Robles - was seen with bullet holes the day after the shooting, the release stated. Two male juveniles were also identified as the other occupants in the vehicle at the time of the shooting.

Robles met with investigators and “provided a voluntary statement of accused admitting his involvement,” the news release stated. He was charged with murder and had his bond set at $1 million.

Two of the other suspects are suspected of fleeing to Mexico, according to the release.

Those with information on the case are urged to contact the Hidalgo County Sheriff’s Office at 956-383-8114.