'On the 7th October 1916, 2nd Lieutenant Mitchell was the officer selected by the 1st Brigade N.Z.F.A. to make a reconnaissance of the local situation regarding Grid Support Trench (Somme). This he did under heavy fire, penetrating in parts beyond our front line, returning at the end of the day with information as our disposition which earned the specially expressed thanks of the Infantry Brigadier and the C.R.A. concerned. The following days 2nd Lieutenant Mitchell was severely wounded and eventually placed on the New Zealand Roll as a result thereof. His record throughout as a gunner and a Commissioned Officer was excellent.'
Source: London Gazette
Date: 1 June 1917