Police Chief David Ferland calls the Thursday incident a "localized event only" and refuses to offer any additional information about the passenger, who surrendered after hours of negotiations.
The 16 other passengers and the driver safely left the bus parked in Portsmouth hours earlier.
The ordeal began late Thursday morning, when a passenger called 911 to report an explosive device on board. That led police to evacuate buildings and streets and call the passengers out under the watch of a sharpshooter in an armored vehicle.
No one was injured, and the holdout passenger is now in custody.
