DETECTIVES investigating the disappearance of university chef Claudia Lawrence are trying to track down two men who they believe could be key witnesses.

Images of both were captured on CCTV near the 35-year-old’s home early in the morning of the day she failed to turn up for work.

But so far, despite an intensive police operation, their identities have not been established and officers are anxious to trace them as soon as possible.

Miss Lawrence was last seen on the afternoon of March 18, not long after finishing her shift at York University’s Goodricke College.

Her disappearance has led to North Yorkshire police’s biggest operation since the hunt for quadruple killer Mark Hobson five years ago - and they are now treating the case as suspected murder.

CCTV footage released yesterday shows a man in Lime Court, just off Heworth Road in York where Miss Lawrence lives.

At around 5.50am on Thursday, March 19 - a crucial period in the investigation - the man is seen to walk from Heworth Road towards the rear of the terrace in where Miss Lawrence’s house is located.

He disappears from view for around one minute, then reappears and walks back onto Heworth Road.

The other man can be seen for a few seconds walking on the opposite side of Heworth Road. He is wearing a light-coloured top and carrying a light-coloured item, which could possibly be a bag or a newspaper.

He was also picked up on CCTV at about 5.55am walking past the Costcutter shop on Heworth Road, on the junction with East Parade and Dale's Lane.

The man leading the inquiry, Detective Superintendent Ray Galloway, said he wanted to speak to the two men as "a matter of urgency."

He added: "I need to ask these two men if they recall seeing anything unusual or suspicious that morning, or even if they possibly saw a woman matching Claudia’s description or any other person who was out-and-about at that early time of day.

"Even the smallest, seemingly insignificant piece of information could prove vital in our efforts to find Claudia.

"So please, if you recognise yourself in the images, get in touch with North Yorkshire Police as soon as possible.

"If anybody else can identify the men then let the police know so we can make inquiries to trace them."

Crimestoppers is offering a £10,000 reward for information which leads to the arrest and conviction of whoever is responsible for Miss Lawrence’s disappearance.

Anyone who can help should contact police on 0845 6060 247 or call Crimestoppers anonymously on 0800 555 111.