The FBI has launched an investigation following a series of homophobic, racist and anti-Semitic incidents at an American university historically known for its tolerance.

Officials at Oberlin College in the US state of Ohio say they have “significant concerns” about homophobic, racist and anti-Semitic graffiti that has turned up in recent weeks.

Campus residents began noticing the campaign of hate in early February. In one instance, a note was left in the Multicultural Resource Center that read “Nigger + Faggot Center.”

In the same month, a poster was defaced to say “Year of the Queer”.

Oberlin College was one of the first university’s in America to allow racial integration between white and black students.

Classes were cancelled on Monday 4 March after a report of someone wearing what looked like a Ku Klux Klan-type hooded robe on campus.

Oberlin College declared Monday “a Day of Solidarity” and President Marvin Krislov said in a statement:

“We hope today will allow the entire community — students, faculty, and staff — to make a strong statement about the values that we cherish here at Oberlin: inclusion, respect for others, and a strong and abiding faith in the worth of every individual. Indeed, the strength of Oberlin comes from our belief that diversity and openness enriches us all, and enhances the educational mission at its core.”

Campus Pride previously gave Oberlin 5-out-of-5 for gay-friendliness.