Commander

The commander of a private army division owned by Henry van Statten remained at the Vault for defensive purposes with the rest of the division.

When van Statten's captive Dalek, nicknamed "Metaltron", escaped from the cage, the commander tried to stop it, with help from the Vault staff. The Ninth Doctor told him that he could blind the Dalek by shooting its eyepiece, but the commander did not heed the Doctor's advice, retorting "I think I know how to fight one single tin robot." He opened fire on the Dalek, which shot at a spot that activated the emergency fire hydrants.

The Dalek shot the water, and the commander, along with the entire battle force, were killed by electrocution.

Biography from the TARDIS Data Core article, licensed under CC-BY-SA