The incident happened in Free Church Passage at about 6.25pm

The victim said she had walked into the passageway from Market Hill when she was sexually assaulted by a man. The attacker then fled towards Bridge Street.

The man is described as a white and about six foot. He wore a black jumper and black gloves.

Detective Inspector Mark Butler said: "This attack left the victim feeling very upset.

"She said the man was startled during the attack by two people who came into the passage from the direction of Market Hill. These people are believed to have been a man and woman - possibly a couple - and I am really keen to hear from them.

"I would like to speak to anyone who was in the area of the Free Church Passage at this time or walking in Bridge Street, or through the town centre.

"Detectives are currently investigating all lines of enquiry but we believe this to be an isolated incident."

Anyone with information is asked to contact DI Butler at Huntingdon Police Station on 0845 456 456 4 or Crimestoppers, anonymously, on 0800 555 111.