Two serious sex attacks on young women are being featured on the BBC's Crimewatch programme.
Police believe that the attacks, which took place in Shrewsbury and Chester, a year apart, were carried out by the same man.
A woman was indecently assaulted as she walked home in Belle Vue, Shrewsbury, in July 2004. Just over a year later, a student was attacked in Chester.
The crimes will be featured on Wednesday's programme.
Det Con Russ Teece of West Mercia Police said: "The case is very much still ongoing.
"This man is clearly extremely dangerous and we are anxious to trace him."
In the Shrewsbury incident the woman was grabbed from behind and pushed to the ground before her attacker ran off. She was distressed but not seriously hurt.
In Chester, a man broke into student accommodation in Cheyney Road and attacked a 22-year-old student. He forced her into a bedroom and attempted to rape her but ran off after she struggled and screamed.