A man was detained and charged with attempting to place an explosive or incendiary device aboard an aircraft, following an alarm was raised by his bag at Pennsylvania’s Lehigh Valley International Airport on Wednesday.

Mark Muffley, 40, of Lansford, Pennsylvania, checked a bag on Monday for a flight to Sanford, Florida, according to the FBI.

The U.S. Transportation Security Administration (TSA) said one of its official located a suspicious item inside the suitcase that appeared to be a live explosive device.

“FBI and local law enforcement bomb technicians determined that the item was indeed a live explosive device,” a TSA spokesperson said.

The bag triggered an alarm and officials found what they described as a “circular compound” hidden in the lining of the baggage, with two fuses and powder concealed in wax paper and plastic wrap, the FBI said in its formal complaint.

The “powder is suspected to be a mixture of flash powder and the dark granulars that are used in commercial grade fireworks,” the complaint added.

“The black powder and flash powder are susceptible to ignite from heat and friction and posed a significant risk to the aircraft and passengers.”

After the alarm went off, authorities paged Muffley to report to security at the airport. Minutes later, Muffley was seen leaving the airport, the FBI added. Later that evening, he was arrested at his home.

Further details on the incident, including Muffley’s alleged intent, were not immediately known. Reuters could not immediately contact Muffley or a representative.

ABC News reported Muffley was due in court on Thursday.

The airport said it had closed a part of its main terminal briefly on Monday while authorities probed the suspicious package.