Police said in a statement that officer Miguel Moreno died Friday morning.
He and his partner were shot Thursday as they approached two men about the vehicle break-in just north of downtown San Antonio. His partner underwent surgery and is expected to survive.
The officers were wounded as they exited their patrol car to speak with the men.
The unidentified gunman died in the exchange of gunfire. Police say the second man was unaware that his companion would pull a weapon and is cooperating with investigators.
VIDEO: Police chief discusses officers' conditions
The chief says the officers were nine-year department veterans. He says they were patrolling after a suspicious-persons report when they spotted the two men. The officers were immediately fired upon when they stepped from their car and returned fire.
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