Marshal of Indian Air Force Arjan Singh is critically ill and has been admitted to the Army Hospital Research and Referral Hospital here, the IAF said on Saturday.
Defence Minister Nirmala Sitharaman visited the former IAF chief in the hospital.
"Marshal of IAF Arjan Singh is critically ill and in Army Hospital R&R.
Hon'ble RM Smt Nirmala Sitharaman visited him in the hospital, " the IAF said in a tweet.
Arjan Singh, 98, was appointed Chief of Air Staff on August 1, 1964.
He was the first Air Chief who kept his flying category till the CAS (Chief of Air Staff) rank.