A 21-year-old man had his phone stolen on Riverside Walk, in Norwich.
On Thursday the man was walking along a footpath towards the city centre when he was approached by a man who asked him the time. The victim took out his mobile phone and told the man, who was carrying a sports bag, it was 12.50pm.
The man, who was described as in his mid 20s and wearing a blue t-shirt, walked past, but returned and demanded the phone.
He became aggressive and the victim gave him his phone.
Police would like to speak a middle-aged male cyclist who was seen on the path at the same time, or anyone else who may have been in the area.
Anyone with any information should DC Sharon Wright at Norwich CID on 0845 456 4567 or call Crimestoppers anonymously on 0800 555 111.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here