The Brady Campaign to Prevent Gun Violence and the widow of a slain Plymouth Township police officer filed a lawsuit Monday against the West Norriton gun store that sold guns to a straw purchaser.

The suit alleges gross negligence by In Site Firearms for selling six guns in a three-month period to a man they should have identified as a straw purchaser. One of those guns was used to kill Officer Brad Fox in September 2012.

According to the suit, In Site ignored several red flags about Michael Henry, including that he was a drug addict who had already purchased several of the same type of gun. Henry always paid in cash and transferred the guns to Andrew Thomas, a convicted felon barred from having firearms, in the gun store's parking lot, according to the suit.

Luke Kelly, owner of In Site Firearms and a retired West Norriton police officer, could not be reached for comment Monday.

Thomas was fleeing from a traffic accident when he fatally shot Fox, and then himself. Henry pleaded guilty to the straw purchases and is serving a minimum 20-year sentence.

The lawsuit is part of the Brady Center's campaign against "bad apple" gun dealers. The center says "60 percent of crime guns can be traced to 1 percent of gun dealers."

Henry bought a total of nine guns for Thomas, the lawsuit says, and eight have yet to be found.

Lynsay Fox, the officer's widow, said Monday that those eight remaining guns motivated her to file the suit.

"I can't bear to think about what those guns are being used for and the other families that may be suffering like mine," she said.

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