Claudia's relationships 'complex'

Det Supt Ray Galloway, of North Yorkshire Police, told BBC One's Crimewatch programme he was certain Miss Lawrence had not told her family or friends about some of her relationships.

The 35-year-old was last seen near her home in York on March 18 and did not arrive for a 6am shift at work the following morning.

North Yorkshire Police have now formally classified the investigation into her disappearance as one of suspected murder.

Nearly 11 weeks since Miss Lawrence went missing, a Crimewatch appeal showed reconstructions of her last known movements and interviews with her father, sister and closest friend.

After the programme, Mr Galloway said he had received calls with information about Miss Lawrence's relationships as a result of the appeal. He said: "We have had information and callers who have either been in a relationship with Claudia, or suspect other people have been in a relationship with Claudia."

The detective said he would trace anyone who had been involved in a relationship with Miss Lawrence and urged those people to come forward now.

The programme also featured previously unseen footage of the inside of the University of York chef's house on Heworth Road and home video footage of her as a child.

Speaking on the programme, Mr Galloway appealed for anyone who had been involved in a relationship with Miss Lawrence to come forward. He said: "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."

The programme also saw Miss Lawrence's sister, Alexandria Sims, give her first interview in relation to the chef's disappearance. Mrs Sims said: "I find it hard to accept that people just vanish into thin air. There must be people out there that have seen something suspicious or who know something that's happened."