Hampshire police have ramped up their investigation into a reported armed robbery which involved the use of a knife in the centre of Southampton.

Officers are hunting a potential witness and want to speak to another man in connection with the incident.

The victim, a man in his 30s, was walking on Argyle Road by the junction with Nichol Road between 3am and 4am on May 6 when he was approached by someone unknown to him.

An unknown man held a knife down by his side and scared the victim by quickly moving towards him, making him think that he might be hurt by the weapon.

An iPhone and £90 in cash were stolen during the incident.

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Hampshire police are now looking to speak to someone in connection with the incident.

He is Asian, five-foot seven-inches tall, of average build and had long black hair with a long black beard.

The man was wearing a black brimless hat, black jacket and black trousers.

Hampshire police are also looking to speak to a "potential witness" who was in the area at the time.

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He is black, approximately six-foot tall, of average build and was wearing a light coloured top and bottoms at the time with a black hat.

Hampshire police said: "If you think you may know the identity of this man, please get in touch with us.

"Officers, who have been carrying out extensive enquiries since the incident was first reported, are keen to hear from anyone with any information which may assist in their investigation.

"Were you in the area at the time of the incident? Do you recall witnessing anything suspicious in the area? Do you have any footage of the incident itself, either before, during or after, including mobile phone, dash cam, doorbell camera, or any other CCTV?

"If you can help us with any of the above questions, please contact 101 and quote incident number 44250195921."