Police searching for a missing Dundee man believe three people seen on Riverside Drive on Sunday morning may hold vital information concerning his whereabouts.
Taylor Frazer, 27, was last seen at the Tesco Riverside supermarket around 4.40am on Sunday.
Police say they have “significant concerns” for his well-being.
It is understood that Mr Frazer, who had been staying at The Malmaison Hotel, was suffering health problems.
A specialist search team has been called in to help find Mr Frazer.
Officers have spent the past two days scouring the Riverside area for signs of him.
Police now say they want to speak to a cyclist, a dog walker and a minibus driver who were seen near the Bridgeview Station Restaurant on Sunday morning as they may hold information that could help trace Mr Frazer.
At around 6.50am on Sunday morning, a man is known to have been cycling eastwards past the restaurant on Riverside and a woman walking her small white dog was also seen in the area at this time.
A Mercedes Sprinter minibus was in the car park there between 4.30am, before being driven off at 9.30am.
The driver of the minibus, cyclist and dog walker are asked to contact officers to establish if there is any information they can provide which can assist in the search for Mr Frazer.
Police officers, with support from Operational Support Division, have been carrying out detailed searches along Riverside Drive towards Dundee Airport to establish where he may have gone from Tesco Riverside on Sunday.
Enquiries at local businesses have taken place and CCTV in the area continues to be reviewed.
Taylor is described as having brown hair and a beard and was wearing a dark coloured, possibly navy blue jacket, denim blue coloured jeans and beige/light coloured shoes when he was reported missing.
A Police Scotland spokeswoman said concerns are increasing for his welfare and anyone with information is asked to contact Police Scotland on 101 or speak to any officer.