New Delhi: Ex-servicemen who are alumni of JNU on Saturday threatened to return their degrees, saying they 'find it difficult' to be associated with an institution that has become a 'hub of anti-national activities' amid a controversy over an event held on the campus against the hanging of Parliament attack convict Afzal Guru.

"We are constrained at the ongoing anti-national activities on the university campus like celebration of Afzal Guru day and consider it an affront to be equated with the present student fraternity of the university which is indulging in such anti-national activities," the ex-servicemen of 54th NDA course said in a letter to JNU vice-chancellor Jagdeesh Kumar.