Prime Minister Narendra Modi and Defence Minister Nirmala Sitharaman today visited the Army Research and Referral Hospital in New Delhi to enquire about the health of Marshal of Indian Air Force Arjan Singh. He was admitted in the hospital following a cardiac attack today morning. The Indian Air Force said, the condition of the 98 year old Marshal is critical. <br/><br/>He is the only officer of the Indian Air Force who was promoted to five-star rank as Marshal. He has served as Chief of the Air Staff from 1964 to 1969 and led the force in 1965 war. He has also served as Ambassador to Switzerland, Vatican and was awarded the Padma Vibhushan.