SAN MARCOS, Texas (AP) — Police say a man who witnesses said fatally shot his ex-girlfriend in the head in Central Texas was later found in his vehicle with a self-inflicted gunshot wound.

San Marcos police said Monday that witnesses told officers 24-year-old Brihana Landrum was shot Sunday morning by 28-year-old Adrian Diaz. Police say they had been involved in an on-again, off-again relationship for several years.

Police say Diaz fled in his vehicle after Landrum was shot. Landrum's family members put her in a vehicle to take her to a hospital, but she died before getting there.

Authorities say that a short time later, Diaz was found in his car in nearby Guadalupe County with a self-inflicted gunshot wound to the head.

Police are investigating the deaths along with the Guadalupe County Sheriff's Department.