Thieves killed a man by running him over with his own car as they drove it away from his Manchester home.
Michael Samwell, 35, caught them in the act after he went to check on a loud bang he heard with his wife in the early hours of Sunday morning, Greater Manchester Police said.
Then they ran him over with his black Audi S3, leaving him with severe injuries. He died after being rushed to hospital.
The thieves fled the scene and the car was found abandoned and severely damaged shortly after the incident.
A murder investigation has since been launched and police are appealing for information.
"My thoughts go out to Michael’s wife and his family, " Detective Superintendent Jon Chadwick. "I cannot comprehend what they must be going through.
“We have now launched a murder investigation and are searching for those responsible.
"This is the murder of an innocent man who has merely sought to protect his property from criminals.
“I appeal for anyone with any knowledge of what happened to come forward... “If you know who has done this you must inform the police of what you know. We will not stop until we have found the person responsible for this dreadful crime.”
Additional reporting by PA