Three men robbed an off-licence in Brighton on Monday night.
They went into the Wine and Beer Store in Norfolk Square, Brighton, at about 10.40pm and attacked the woman who was working there before stealing the till.
The robbers hit her over the head although it is not clear what they used as a weapon to hit her with.
She was taken to the Royal Sussex County Hospital to have a minor head injury treated and was later disacharged.
A dark 4×4 vehicle parked outside the shop is believed to have been used by those carryout the robbery.
All three men had their faces covered.
Anyone who saw the men, the vehicle or who knows of the whereabouts of the shop till is asked to contact Sussex Police on 0845 6070999.