Lt Col Gordon Mackenzie said:
"I have the tragic duty to report that six soldiers are missing, believed killed, during a security patrol. The six soldiers were on patrol in a Warrior Armoured _Fighting Vehicle when it was _caught in an explosion."
The Ministry of Defence says the soldiers' next of kin have been informed of the incident.
Lt Colonel Zac Stenning, of 3rd Battalion The Yorkshire Regiment, read a eulogy to the men outside Battlesbury Barracks in Warminster.
Six soldiers have been killed, after an armoured vehicle was caught in an explosion in Afghanistan.