Duke University officials say a professor criticized for an online statement comparing blacks and Asians had been on a standard academic leave before posting the comments.

In response to a May 9 editorial on racism by The New York Times, political science professor Jerry Hough compared "the blacks" and "the Asians." He wrote in his online comment that Asians faced racism but "worked doubly hard."

Criticism included a statement from a university spokesman that Hough's comments were "noxious" and "offensive."

The chairman of the university's political science department, Jack Knight, said in an email that Hough was on an academic leave unrelated to the comments.

Knight said that Hough was granted academic leave last year for the 2014-15 school year under the standard policy for faculty.