Thieves attacked a security guard before making off with a cash box at NatWest Bank.
The cash-in-transit guard fell to the ground unconscious during the assault shortly after 11.30am in Finchley Road, Temple Fortune, yesterday.
The two men then left the bank, got into a car and made off.
Paramedics took the security guard to hospital.
No arrests have been made. Both suspects were wearing dark clothing and had their faces covered with balaclavas.