FAMILY and friends of missing chef Claudia Lawrence marked a sombre milestone yesterday.

It is now 100 days since the 35-year-old vanished without trace and despite a huge police investigation her whereabouts remain a mystery.

But her family are refusing to give up hope - and used the anniversary of her disappearance to launch a specially-commissioned four-minute film on the internet.

In the film - which can be seen on The Northern Echo’s website -her father, solicitor Peter Lawrence, makes a worldwide appeal for information that could help find his daughter.

"Ever since Claudia disappeared, it’s just felt as though there’s something missing, a part of me missing," said 62-year-old Mr Lawrence.

"She’s a big part of my life that’s not there any more and that’s hard.

"Obviously, I frequently think about it and I can burst into tears. Even when I’m doing press conferences and TV interviews, it’s all right on the outside, but I’m very churned up on the inside."

The family are hoping that the film will be widely viewed on the internet and it has been posted on the You Tube site.

Family spokesman Martin Dales said Mr Lawrence believed his daughter could be anywhere and added: "He feels the worldwide audience of the web is vital to her being found."

In the film Mr Lawrence makes a heartfelt plea for anyone who knows anything about his daughter and has yet to speak to police to come forward.

"There is someone out there," he says.

"If you are that somebody you should jolly well be saying so because there is no point in protecting anyone’s relationships or lifestyle in the situation that we are in.

"This is potentially a murder investigation. It’s just not fair to Claudia’s family – to me, to her sister, Ali, and to her mum. Please just say something."

Miss Lawrence was last seen on March 18 after she had completed her shift as a chef at York University’s Goodricke College.

Police have since mounted their biggest investigation since the hunt for quadruple killer Mark Hobson five years ago - and are now regarding the case as one of suspected murder.

The charity Crimestoppers is offering a reward of £10,000 for information leading to the conviction of the person, or persons, responsible for her disappearance.

Anyone with information should contact police on 0845 6060 247 or Crimestoppers on 0800 555 111.