A man accused of threatening to open fire at the world’s busiest airport in Atlanta was arrested Monday and an assault rifle was found in his car, police said.

Police said at a news conference that 49-year-old Billy Joe Cagle, of Cartersville, Georgia, had described his plan during a video call with family members. Authorities described him as a convicted felon.

Police said they found an AR-15 rifle and 27 rounds of ammunition in his pickup truck nearby after he was taken into custody Monday inside the domestic terminal at Hartsfield-Jackson Atlanta International Airport.

“We’re here today briefing you on a success and not a tragedy because a family saw something and said something,” Police Chief Darin Schierbaum said.

Cagle is charged with making terroristic threats, criminal attempt to commit aggravated assault, possession of a firearm during the commission of a felony and possession of a firearm by a felon, Schierbaum said.

Atlanta Mayor Andre Dickens said “we’re thankful to God” that a tragedy was averted.