Transcript for Video shows woman being fatally shot as she set up garage sale

This evening, the manhunt for a killer in Texas is under way, after a woman was killed while setting up a garage sale. Surveillance showing the gunman proaching the woman in her driveway, exchanging some words and then firing point blank. Tonight, police are now asking for the public's help, and ABC's Marcus Moore is on the scene. Reporter: This terrifying surveillance video showing Elizabeth Barraza's execution-style murder has investigators outside of Houston puzzled. Just four minutes after her husband left for work, the 29-year-old was murdered while setting up a garage sale in her own driveway. That suspect, shooting Barraza four times at point blank range early in the morning on Jon 25th, then running away on foot before driving off in this dark-colored truck. Police say it's unclear whether Barraza was targeted. She had only put out signs for that garage sale that morning. And investigators don't even know if the shooter is a man or a woman. Definitely it is possible they were trying to disguise their appearance. Reporter: Her family making a plea for the public to help find the killer. We had to trade our fifth anniversary for her funeral. Reporter: And David, this garage sale in the driveway here was to raise money for an anniversary trip with her husband. Authorities say they have generated new leads overnight, but this case remains a mystery. David? All right, us, thank you.

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