ATLANTA — Police arrested a man at Atlanta's bustling airport on Monday after getting a tip from his family that he was planning to shoot up the place, and found an assault rifle and ammunition in his truck outside, the city's police chief said.

Billy Joe Cagle, of Cartersville, Georgia, had described his plan to shoot up the world's busiest airport on a social media livestream, Chief Darin Schierbaum said during a news conference.

“The Cartersville Police Department was alerted by the family of Mr. Cagle that he was streaming on social media that he was headed to the Atlanta airport, in their words, to ‘shoot it up,’ and the family stated that he was in possession of an assault rifle,” Schierbaum said, describing Cagle as a “convicted felon.”

Cagle, 49, arrived at Hartsfield-Jackson At

See Full Page