Dive teams have been deployed in the search for a man who has been missing for almost a week.

Police are increasingly concerned for the welfare of Viktor Vaimel, who was last seen in Rickmansworth on Saturday, July 3 around 10am.

He is "considered" to be vulnerable by police.

With searches for the 41-year-old having been on going for five days, specialised dive teams are now conducting searches of the River Chess, Hertfordshire Constabulary said.

The force wrote on Facebook: "As part of our continuing enquiries to trace missing 41 year old Viktor Vaimel, specialised dive teams are conducting searches of the River Chess today (Thursday 8 July) for any clues as to his whereabouts."

Viktor is described as 5ft 10in tall with short brown hair and blue eyes. He is believed to have been wearing blue jeans with a white T-shirt, white trainers and a black jacket. Police say he is a smoker.

He has links to Tottenham and often travels by train.

Today's appeal (Thursday) is the third issued by police since his disappearance was first made public on Sunday afternoon.

Anyone who spots Viktor is asked to call 999 straight away, whereas anyone with information on his whereabouts can call 101 quoting ISR 421 of 3 July.