An Indianapolis police officer mistakenly shot and badly wounded an armed homeowner who was trying to protect his wife during an attempted robbery early Tuesday, authorities said.

The shooting happened at around 4:30 a.m. after police were called about the robbery in a subdivision on the city's far east side. Assistant Chief Randal Taylor said a woman was confronted in her driveway by a young man who pointed a gun at her head and demanded her car keys.

She threw the keys at the gunman, ran into the house and her husband came outside with a gun at around the time officers were arriving, Taylor said.

"The vehicle that was the target of the carjacking and robbery was still in the driveway," Taylor said. "Officers weren't initially sure if the suspect was still with the vehicle. The husband was out with the weapon, and unfortunately the husband was shot by one of our officers."

Taylor said the homeowner was in serious but stable condition at a hospital with an abdominal wound.

The gunman who tried to steal the car, described as in his late teens, fled from the scene and was being sought.

Taylor said the shooting is being investigated and that the officer, whose name wasn't released, has been placed on administrative duty pending the outcome.

"Obviously the homeowner had a weapon out, but I'm not sure what conversations would have occurred, if any, between the officer and the homeowner," he said.

The wounded man didn't apparently fire any shots and his wife wasn't injured, authorities said.

"Our prayers and thoughts are certainly with him and his wife and the rest of their family," Taylor said. "It's just an unfortunate occurrence."