The outgoing Defence Adviser at the Australian High Commission in Sri Lanka, Group Captain Sean Unwin and incumbent Defence Adviser Captain Ian Cain paid a joint courtesy call on the Chief of Defence Staff, Army Commander and Head of the National Operations Centre for Prevention of COVID 19 Outbreak, Lt. Gen.Shavendra Silva at the Army Headquarters on Monday (30). The Australian Defence Adviser, paid his gratitude to the Commander for the cordial relationship during his tenure of office in the country.