A robbery took place at the Cheque Centre, Foundry Walk, Daventry on Monday morning.
A 48-year-old woman was confronted by a man as she arrived at work at about 8.20am. The man threatened her with violence and demanded money from inside the shop. The woman handed over cash and the man tied her to a chair before making off. The woman was not injured in the incident but was left shaken.
The offender was a black man, aged 20 to 25, about 5ft 5ins and with with a medium build. He wore a blue scarf over his nose, a blue hooded top and grey/blue jeans. He was carrying a rucksack and had a lighter patch of skin by his left eye.
Police would like to speak to anyone who may have witnessed this incident or who may have any information regarding it. Witnesses or anyone with information is asked to contact police on 101 or Crimestoppers anonymously on 0800 555 111.