Detectives have warned women in one of the UK's most famous student cities after linking a string of sex attacks.
Police said they thought the same man had "sexually touched" women as they walked in Cambridge over a three-month spell.
A police spokesman said some victims were students and officers were warning women to be cautious when in the city.
He said experts were trying to create a photofit image of the attacker - and urged anyone with information to get in touch.
Victims have described the man as white, aged 20 to 30, 5ft 10in to 6ft, of medium build and physically strong.
Police said the man is thought to have short dark hair and stubble, and to be wearing a black jacket over a grey hooded jumper.
The spokesman said that in every incident women had been "grabbed" as they walked.
"Police are linking six incidents which have occurred in the city since November 11," said the spokesman.
"In every incident the offender has run off when the victim began struggling or screaming."
He added: "We have spoken to universities and are warning women to be cautious. We are also increasing patrols."
Detective Inspector Billy Bremner said: "These six unpleasant incidents have striking similarities and we are linking them at this time.
"I would appeal to anyone with any information regarding these incidents to contact police."
Police said five women had been attacked between November 11 and Christmas Day - a sixth was then assaulted on February 7.
The spokesman said:
:: At 1.15am on November 11, a 21-year-old woman was grabbed in Adams Road;
:: A 29-year-old woman was assaulted in Silver Street at about midnight on November 17;
:: The following day, at around the same time, a 21-year-old woman was assaulted in Sidgwick Avenue;
:: A 19-year-old woman was grabbed in the same street at 2am on December 2;
:: A 32-year-old woman was assaulted in Granchester Meadows at 3am on Christmas Day;
:: The latest incident happened in the early hours of February 7. A 27-year-old woman was grabbed in Shelly Row at 12.30am. The offender ran off when she screamed.Reuse content