THE detective investigating the disappearance of Claudia Lawrence said he has received vital information about people involved in relationships with the university chef.

More than 40 calls were received after the case – now classed as a suspected murder – was featured on BBC1’s Crimewatch last night.

Detective Superintendent Ray Galloway, of North Yorkshire Police, said: “Critically, we have had information from callers who have been in a relationship with Claudia or suspect other people who have been in a relationship with Claudia.”

The 35-year-old was last seen near her home in Heworth Road, York, on March 18.

Earlier, Det Supt Galloway told the programme: “As the investigation has developed, it’s apparent that some of Claudia’s relationships had an element of complexity and mystery to them. I am certain that some of those relationships were not known to her family or her friends.

“I’m not here to judge Claudia’s relationships, I’m here to investigate them. I need people to share that information with me.”

Her friends and family have previously dismissed speculation that she may have had a secret boyfriend.

Miss Lawrence’s sister, Ali, also appeared on Crimewatch, together with her father, Peter, mother Joan and close friend Suzy Cooper.

Speaking about her sister’s disappearance for the first time, Ali said: “There’s frustration at not knowing what’s happened to her, because obviously someone must know what’s happened, and someone must know someone else who knows what happened.”

The programme also featured reconstructions of Miss Lawrence’s last known movements and of possible sightings since.

Anyone with information is asked to call 0845-60-60-24-7 or Crimestoppers, which has offered a £10,000 reward, on 0800-555-111.