TD Garden officials are investigating after a fire alarm went off Wednesday night, triggering an evacuation of the arena about an hour after the Boston Celtics playoff game against the New York Knicks, officials said. “The cause of the fire alarm is currently under investigation,” according to a TD Garden statement Thursday.

Following the Boston Celtics’ 91-90 loss to the New York Knicks in Game 2 of the East Semifinals on Wednesday night, TD Garden had a strange event take place. Shortly after the game concluded, the arena’s officials had to evacuate fans out of the building due to a fire emergency.