Police are hunting the man following the incident at Premier convenience store, Victoria Road North, on Sunday, at 8pm.
‘A man entered the store and threatened a staff member with a knife, before taking around £100 cash from the till and a number of packets of cigarettes from behind the till,’ a police spokeswoman said.
Thunderstorms in Portsmouth yellow weather warning: The Met Office forecast for the next three days in city, Fareham, Gosport, Havant and Waterlooville and Hampshire
Police update on probe into death of ‘Wiggy’ Symes after fatal dog attack in Fareham
Emergency crews battling to save someone’s life on Southsea seafront
Southsea seafront incident: Police update after man found 'unresponsive'
River Ems crisis: Westbourne villagers plead with Portsmouth Water to introduce a hosepipe ban
‘He then cycled down Stansted Road towards Fawcett Road.’
Police have released an image of the man they are tracking. He is described as around 5ft 11in tall, white with a ‘proportionate build’ who was wearing a dark hoodie with a white zipper.
He also had a vertical white zipper on the left chest pocket and white piping on the hood, black trousers, black trainers, a balaclava or mask and black gloves and was carrying a green Asda bag.
‘We know the image isn’t clear, but it’s the best we have available at this time,’ the spokeswoman added.
‘We would like to hear from anyone who was in the area at the time and may have seen or heard anything.
‘We would also like to hear from anyone who may have CCTV or dashcam footage of the area at the time, or anyone who thinks they have been offered cigarettes for sale in suspicious circumstances.’
Anyone with information should call 101 quoting reference 44210037566 or Crimestoppers anonymously on 0800 555 111.