Miss Lawrence's father said it is 'dreadful' police have been

Police investigating the disappearance of Claudia Lawrence six years ago have searched an alleyway behind her home amid suggestions a secret lover may have killed her.

Officers cordoned off the alley this morning after the police chief in charge of the new inquiry predicted arrests 'in the coming weeks and months'.

Detective Superintendent Dai Malyn said it is possible Miss Lawrence was killed in her home on the night of March 18, 2009 by a lover who then left by the alleyway.

Nobody has seen or heard from Miss Lawrence since she came home from work in March 2009 and failed to return the following day. The university chef would have celebrated her 41st birthday on Friday.

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Claudia Lawrence: Nobody has seen or heard from the missing university chef since she returned from work in 2009. She would have been 41 on Friday

Still missing: Police believe the disappearance of Miss Lawrence is linked to her private life. The new operation will focus on the alley at the back of her house in York and will include house-to-house enquiries

Police are hoping the new search will shed light on what happened to Miss Lawrence in March 2009

Detectives taped off and searched an alleyway which runs behind Miss Lawrence's terraced home

North Yorkshire Police officers and a sniffer dog focused on the dirt alleyway behind her red-bricked terrace home in Heworth Road, York, today, lifting paving slabs and moving bins.

DS Malyn of North Yorkshire Police said: 'One hypothesis is something could have happened overnight with another person in the house and then the alleyway was an obvious way out.'

He added: 'I know people have lied to us. People may lie because they are in a relationship, and there could be a number of reasons why they are withholding information.

'We have significant leads, my team and myself are determined that if anybody is lying to us we will be arresting people because I am convinced people have information which they are not telling us about. We need to eliminate people who have previously not come forward.'

Fingerprints have been lifted from Miss Lawrence's home and Det Supt Malyn urged anybody who has had a relationship with her to contact the police.

Miss Lawrence's father, Peter, today said it is 'dreadful' that people may have been lying to police investigating his daughter's disappearance.

He said: 'It's obviously absolutely dreadful that anyone would do that.

'We know that people lie to the police but in a case like this that involves Claudia's disappearance and everyone can see what it's done to the the family... come on.'

New lead: Miss Lawrence's father Peter spoke today as police taped off the lane behind her home

North Yorkshire Police have 20 officers working on the new probe after a detective said: 'Somebody lied to us'

Miss Lawrence was last seen as she returned home from work from Goodricke College in March 2009. The original investigation included a search of her local pub, The Nag's Head

Speaking at his house in York, Mr Lawrence added: 'The police told me that they were going to be down there because they thought there was significance in the alleyway at the rear of the house - basically that's all I know.

A FATHER'S AGONY: PETER LAWRENCE ON THE NEW PROBE Mr Lawrence said today: 'Friday is Claudia's 41st birthday, so that's the sixth birthday that we've had to do without her company and her jollity. It's a long time. 'It's difficult all the time but when there's a birthday, when you get the anniversaries and at Christmas it's just worse. Claudia ought to be with us. How might she have changed in six years? What have we missed in all that time? 'The police told me that they were going to be down there because they thought there was significance in the alleyway at the rear of the house - basically that's all I know. 'It's a criminal investigation and they need to be careful about what they say. 'I think it's just positive that they are looking, They've got a team out and they're still active and it keeps it in the public eye. 'Somebody clearly does know what happened and maybe from a misguided sense of loyalty they've kept quiet. Hopefully this very thorough investigation, and keeping it in the public, will make them change their mind.'

'It's a criminal investigation and they need to be careful about what they say.

'I think it's just positive that they are looking, They've got a team out and they're still active and it keeps it in the public eye.'

Mr Lawrence said: 'Somebody clearly does know what happened and maybe from a misguided sense of loyalty they've kept quiet. Hopefully this very thorough investigation, and keeping it in the public, will make them change their mind.'

Mr Lawrence said: 'Friday is Claudia's 41st birthday, so that's the sixth birthday that we've had to do without her company and her jollity. It's a long time.

'It's difficult all the time but when there's a birthday, when you get the anniversaries and at Christmas it's just worse. Claudia ought to be with us. How might she have changed in six years? What have we missed in all that time?'

Fresh forensic examinations have also recently been carried out at Miss Lawrence's former home, which has remained empty since her disappearance.

Det Supt Malyn said: 'The review remains very active and the team are currently working on a lead that may indicate the alleyway at the rear of Claudia's house is significant.

'I have always thought that if something happened to Claudia inside the house then the most obvious route out would be to use the alleyway.'

Search: Police with sniffer dogs scoured a lane behind her home in Heworth Road, York this morning

Officers made door-to-door enquiries today after a detective said arrests could be made in coming weeks

Police have urged all of Miss Lawrence's previous boyfriends and lovers to come forward and speak to them

A 20-strong team of officers have been tasked with the fresh investigation into what remains one of the most puzzling unsolved crimes in the country in recent years.

I know people have lied to us. People may lie because they are in a relationship, and there could be a number of reasons why they are withholding information Detective Superintendent Dai Malyn

Det Supt Malyn added: 'We still don't know if Claudia left for work on the morning of Thursday 19th March 2009 or whether something happened overnight within her house.

'If the latter is the case the person or persons responsible, in my view, would have used the rear alleyway as the front door leads onto a busy main road. This is why this specific piece of information needs to be fully investigated.'

The move came after police revealed they had a new lead in the case which indicated the alleyway was 'significant'.

DS Malyn said the alleyway lead was one of 'several active enquiries' being looked at by the team.

DS Malyn said: 'Together with Claudia's family, we remain absolutely determined to solve this case and bring those responsible for her disappearance and suspected murder to justice.'

Officers were seen outside the Nag's Head pub which was searched in the days after her disappearance

Arrests: The detective in charge of the investigation says he believes arrests may be made in coming weeks

North Yorkshire Police are committing significant resources to the new investigation into the disappearance

Nobody has seen or heard from Miss Lawrence since Wednesday 18 March 2009.

She returned home from work and spoke to her parents in separate phone conversations that evening but never arrived for her early shift at work the following day.

She was reported missing by her father Peter Lawrence, a solicitor, on the Friday after he was contacted by a worried friend.

Despite a huge operation police have found no clue to indicate what may have happened to her, but they have always believed her disappearance was likely to be linked to her private life.

A new review – under a new team of officers – was launched in October 2013 and has continued ever since.

DS Malyn said earlier this week that the new team has been 'able to spot' things that didn't seem significant at the time she vanished and prioritise them.

'I am convinced the breakthrough in the investigation will be from the relentless pursuit for the truth.

Officers are appealing for anyone with information to come forward, saying it could provide the breakthough

Police carried out fingertip searches of the alley they believe could have been an escape route for a killer

Detective Superintendent Dai Malyn North Yorkshire Police's enhanced Major Crime Unit at the scene today

DS Malyn added: 'When that person or persons with the vital information makes the right decision to share it with us Claudia's family will finally get some answers that they are still desperately searching for.'

Last May a 60-year-old man was arrested in York on suspicion of Miss Lawrence's murder. He was later released from his bail without any further action being taken.

A man of 47 arrested in July on suspicion of perverting the course of justice remains on police bail.