A student at an upstate New York college caused an uproar by posting "white only" and "black only" signs around the campus as part of an art project.

The graduate student at the State University of New York at Buffalo says the display was meant to provoke dialogue about racism. Instead, the signs shocked some students.

University police received calls from students who said the signs traumatized them. They have been taken down.

The student, Ashley Powell, is black, and said she started posting the 17 placards on Wednesday in campus buildings to "expose white privilege."

A school spokesman says the SUNY community needs to discuss how to balance academic freedom with a safe environment.