Updated

Duke University says a student who left a noose hanging on campus has been disciplined but can return to campus next semester and won't face criminal charges.

The university on Friday also released an apology letter written by the person responsible, who says the noose was made as a joke and carelessly left outside. The letter says the person didn't know its connection with lynching in the South.

The letter states: "Once I realized the historical connotations, I contacted the Administration, and explained that I never had any racist intent."

The university news release said the noose, which was found April 1, was left as a result of ignorance and bad judgment. It says investigations by the school and law enforcement have concluded.

The student hasn't been identified.