Detectives investigating a murder in Colchester may have new information following an appeal on Crimewatch.
The BBC show featured the murder of Nahid Al-Manea last night and Essex Police said the public response has been "encouraging".
In particular they are looking into a person of interest after being given a name by a caller following the initial show.
Saudi Arabian student Nahid, 31, of Woodrow Way, was stabbed 16 times on the Salary Brook Trail shortly before 10.40am on Tuesday, June 17.
She was on her way to a class at Essex University when she was killed on a bright sunny day by a path used by many people, particularly students.
Det Chief Insp Lucy Morris, who appeared on the BBC1 show, said: "It was extremely useful to appear on Crimewatch to make an appeal for information.
"There have been several calls to the incident room as a result of the show and we are sure these will help us with our investigation.”
In particular the police want to speak to a number of people spotted on the trail around the time of the murder who have not yet come forward.
- A man wearing a beige Italian designer jacket, slightly longer than waist-length, had brown buttons up the front and two pockets also with buttons.
He was seen on the Salary Brook Trail between 10.20am and 10.40am, shortly before Nahid was found.
He was walking towards the Greenstead estate on the Salary Brook Trail.
He has thick, short black hair and is aged between his late teens to 30s, 5ft 6ins tall and was of average build.
• Two cyclists who were seen using the trail and may have seen Nahid after she was attacked.
They were seen by a witness at 10.45am on Tuesday, June 17, coming from the direction of the university towards Greenstead on the Salary Brook Trail.
The man is olive skinned with dark hair. He was in his early 20s and looked tall and slim.
The woman is thought to be in her 20s with long dark hair. She was wearing a flowing pattern tiered skirt.
• A tall man in a trilby style hat who was seen in the area around the time of the murder.
He is slim and was wearing a long dark trench style coat. His hat may have been green or dark blue and he had long dark wispy hair.
• A white man, aged between 19 and 23-years-old, with blond hair. He is thought to be English and was wearing a back pack and white headphones. Witnesses describe him as looking like a student.
• A white man also thought to be a student, who had dark, short hair. He was wearing light trousers and was using a phone.
• A black man who was wearing a forward facing cap and a back pack. He was also wearing a dark blue and yellow striped polo top.
• Two women on bikes, who were seen by the hedgerow on the Salary Brook Trail • A white woman with long blonde hair, 5ft 10ins tall, of slim build and aged around 19 or 20. She is described as possibly being a foreign student.
• A young man on a bike, also seen on the Salary Brook Trail.
It is the third time murders in Colchester have appeared on the show in recent weeks.
An appeal and a reconstruction featured on the show in different weeks following the murder of JIm Attfield.
The 33-year-old father-of-five was stabbed 102 times and found shortly before 6am on a path between Castle Park and Guildford Road, Colchester.
Anybody with information call the incident room on 01245 282103 or Crimestoppers anonymously on 0800 555 111.
Independent charity Crimestoppers has offered a £10,000 reward for information that leads to the conviction of the person or people responsible for the death of Nahid, Jim, or both.
Separate but parallel investigations are being carried out into the murders.
Detectives have not ruled out a connection.