Juan Zigler allegedly handed clerks at the Marathon post office a garbled threatening note on which he wrote that he would "blow up the hole Florida Keys" on Friday, according to a news release from the Monroe County Sheriff's Office.
The 69-year-old Marathon man then reportedly threw an object over the counter which initially looked, to the clerks, like a firecracker.
Apparantly Ziegler didn't have a getaway plan: The clerks called 911 and when a deputy responded Zigler was still in the post office.
The object Zigler threw was a dud; it appeared to be some sort of battery with a wire attached to it, the release stated.
Zigler was charged with making a false report of a bomb and with manufacturing or delivering a hoax bomb. He was booked into jail.