Ex-NFL Player's Mistress Kidnaps and Kills His Wife in Murder-Suicide: Police
07/18/2015 AT 01:55 PM EDT
Clayton County police allege that Lisa Brown, of Lithonia, Georgia, kidnapped Sandra Barnett, of Ellenwood, Georgia, from her home Wednesday, according to the Atlanta Journal-Constitution.
Sandra, 58, is the wife of Buster Barnett, who played for the Buffalo Bills in the '80s.
"Sandra was actually on the telephone with a friend when Lisa showed up at the front door," Capt. Richard Gandee told 11 Alive.
Police also allege that Brown, 49, had purchased handcuffs before the abduction, according to 11 Alive.
Brown's Dodge Durango was spotted Thursday, police said, and the ultimately fruitless pursuit ended in eastern Alabama – where both women were found dead of gunshot wounds after Brown allegedly stopped the vehicle in the middle of the interstate, shot Sandra and then turned the gun on herself, authorities told 11 Alive.
Brown – who drove a car and lived in a home owned by Buster, 56, police told the AJC – allegedly became angered by the news that the married couple would be going on a trip, police said, and she confronted Buster on Wednesday before abducting his wife.
"She was upset about a trip that his wife was going on with him and it was one she didn't know about," Clayton County Police Officer Charlene Watson-Fraser told the AJC.
Clayton County police did not immediately respond to PEOPLE's request for comment.
Both women were school teachers, according to the station.
Brown was convicted in 2015 for kidnapping her daughter two years earlier, according to 11 Alive.
Sandra's co-worker remembered her this way: "Everybody just remembers this bubbly, happy spirit – just happy. Every day at work, you could just count on her."
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