Basic Details Surname O'Brien Forenames Dermot Gender Male Information stated on memorial Served or died Died Primary Service As stated on memorial Unit (Primary - Stated) Royal Regiment of Artillery Our References Service (Primary - Our reference) British Army Unit (Primary - Our reference) Royal Artillery Death and Burial details Country of death Belgium Town of death Ypres Year of death 1917 Month of death September Day of death 26 Manner of death as stated Killed in Action Manner of death reference Killed in Action