(Chapel Hill, N.C.) (AP) — The head of North Carolina’s flagship university says activists who tore down a century-old Confederate statue this week took campus officials by surprise.

Chancellor Carol Folt said Thursday that the University of North Carolina at Chapel Hill expected about 100 people to peacefully protest the earlier arrest of an activist demanding removal of the memorial nicknamed “Silent Sam.”

Instead, a larger crowd gathered and dispersed, and then protesters returned to yank down the statue as banners hid their actions from police.

Folt says officials haven’t finished investigating what happened Monday night, but there have been dozens of campus protests in her five years on campus. She says all were handled in ways that seemed appropriate at the time.

The bronze statue erected in 1913 is in temporary storage.