A woman was sexually assaulted in Oxford by a man who grabbed at her while riding past on his bike.

At 7.30am on Friday the man was riding along Old London Road near the Churchill Hospital when he grabbed at the woman’s clothing as she was walking along the pavement.

He was riding a bicycle with a light under the saddle and was wearing blue jeans, white trainers, a grey top with red sleeves and a hood.

He was carrying a white patterned backpack with a black base.

PC Matthew Richardson, of Thames Valley Police, said: “We are looking for the victim to come forward in relation to this sexual assault which has been witnessed, but not reported.

“The incident appears to be a random sexual assault in which a cyclist has grabbed at a woman as she has been walking along the footpath before speeding off.

“We would like to trace the offender to try and prevent it from happening to anyone else.

Similarly if this has happened to anyone else we would like them to come forward."

Anyone with information should call 101, or Crimestoppers anonymously on 0800 555111.