On Mar. 11, United flight UAL3613 departed Newark (EWR) and was enroute to Burlington, VT (BTV) and was about 20 minutes away when a passenger found a note in the aft lavatory stating there was a bomb on board. The passenger notified cabin crew who then passed the message to the flight deck. The flight crew then notified ATC about the issue, which prompted a massive law enforcement response at Burlington, ultimately closing the airport for several hours. Multiple agencies including the FBI & Dept. of Homeland Security were on scene to assist in the investigation. The flight landed around 4:30pm and was taken to a remote area on the tarmac where passengers remained on the plane for ~2 hours before disembarking. No credible threat was found, and the investigation is still ongoing.