The scientist who prompted an evacuation of Miami International Airport for carrying what screeners believed was a pipe bomb is known to federal authorities and was charged in 2003 for illegally transporting 30 vials of the deadly bubonic plague.
Officials said Dr. Thomas Butler, 70, a U.S. citizen, who teaches in the Caribbean and Saudi Arabia, was released after questioning. Authorities said the metal canister in his luggage tested negative for dangerous materials and was related to a legitimate experiment.
Butler, a renowned infectious disease expert who spent more than 20 years working on cures for cholera and bubonic plague at Texas Tech, lost his job after he was found guilty of exporting the vials, lying to federal officials, and embezzling research funds. He was charged with 47 counts smuggling biohazard materials. He spent two years in prison but was later acquitted of smuggling plague pathogens.
Bubonic plague, an ancient disease that causes victims' glands to painfully swell before causing death, is one of several viruses and bacteria that anti-terror experts fear could be used as a terror weapon. Some antibiotics have proved useful in treating plague, and Butler reportedly was reportedly working on a new cure while at Texas Tech in Lubbock.
Officials said Butler, whose name they have yet to release publicly, was cooperative and permitted to continue his trip after questioning. At a press conference today, FBI agent Michael Leverock called him "very cooperative."
Butler was reportedly travelling from Saudi Arabia. He changed planes in London and was switch planes in Miami before ending in San Juan, Puerto Rico.
Officials said Butler is a professor at Ross University in the Caribbean and was on teaching assignment in Saudi Arabia.
Most of the airport was shut down for several hours late Thursday night after officials found the metal canister in Butler's luggage.
Authorities initially suspected it was a possible pipe bomb and evacuated the airport.
Passengers from four of the airport's six concourses were evacuated as the bomb squad scoured the airport.
The airport reopened early today.
The Miami airport incident was the second terror scare in recent days that turned out to be unfounded. Last week two Yemeni men was taken into custody in Amsterday and suspected of being on a "dry run" for a terror attack. They were later released and found to have no connection to terror.
The Associated Press contributed to this report.