Law enforcement agencies executed a search warrant on the home of a man believed to have sold the weapon used in a West Texas shooting Saturday, ABC News confirmed.

Officers searched a home in the Lubbock area Wednesday night, according to ABC.

On Saturday, accused shooter 36-year-old Seth Ator killed seven people and wounded more than 20 in a shooting rampage across Midland and Odessa. He obtained the AR-style gun in a private sale.

Ator had previously failed a federal background check for a firearm, said John Wester, an agent with the federal Bureau of Alcohol, Tobacco and Firearms.

According to federal law, a private seller may not sell to a person who is flagged, but the seller isn't required to conduct a background check or ask the buyer's status, ABC says.

RELATED: West Texas shooter got AR-style weapon used in rampage through private sale

That loophole is how Ator was able to purchase the gun in the first place.

A separate report from the Wall Street Journal also confirmed the Lubbock search warrant news.

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