Zeljko Causevic, 39, remained silent during his brief hearing before Duval County Court Judge Russell Healey on charges of making a false report about planting a bomb and possessing a hoax bomb.
According to a Jacksonville Sheriff's Office arrest report, Causevic, a naturalised US citizen, approached a Transportation Security Administration agent yesterday, saying he had a device in his camouflage backpack that was "supposed to be a bomb, but it's not." Inside the backpack, officials found a small luggage scale with two batteries and a microchip. He told authorities he had a "detonator," which was a remote control device, and his bag also contained a cellphone.
The threat shut down the airport for about five hours last night, delaying outbound flights and stranding passengers on planes on the tarmac.
It was unclear whether Causevic was getting onto a flight, and authorities have not released a motive. The FBI, airport police and the Jacksonville Sheriff's Office are continuing to investigate.
Phone numbers listed for Causevic were disconnected.
Another man who was acting suspiciously was arrested at the airport about the same time Causevic was taken into custody, but authorities said the arrests were not related.