Police hit back last night at criticism that detectives missed vital clues that should have led them more quickly to the house where Shannon Matthews was found.

Since the nine-year-old was discovered on Friday several residents have come forward to claim that they provided information that West Yorkshire Police allegedly failed to act upon. A source close to the investigation has told The Times that some of the so-called tip-offs were baseless, while others contained inadequate information. Suggestions that Mick Donovan, the man being held on suspicion of Shannon’s abduction, should in any case have been a higher priority for investigation are also dismissed by force insiders.

Details have emerged of the scale and complexity of the inquiry that was launched after the girl was reported missing on February 19. In addition to the intensive search that was carried out by hundreds of uniformed officers in Dewsbury Moor and surrounding areas, from day one a team of 60 detectives began to amass a list of potential suspects in the locality.

Separate teams, each split into smaller units, focused on members of Shannon’s extended family and known or suspected sex offenders living in or near Dewsbury. Where the same name appeared on both lists, as happened in several cases, those individuals were inevitably treated as the highest priority for intense scrutiny.

Almost 1,400 registered sex offenders live within a 20-mile radius of Shannon’s home. To that list was added the names of historic sex offenders whose convictions predated the creation of the register in 1997, plus those who had been arrested on suspicion of sex offences but not convicted.

Drawing up a list of the many hundred members of the missing girl’s extended family proved such a complex task that it had not even been completed before the child was found.

Shannon’s mother, Karen Matthews, has seven children by five different fathers, plus a number of former partners. Added to her relatives, plus her boyfriends’ and children’s fathers’ close relatives, were the relatives of Shannon’s natural father, Leon Rose, and her stepfather, Craig Meehan, 22.

The Times understands that several people who formed part of Shannon’s extended family had criminal convictions for a wide variety of offences, some of them – but not Mr Donovan – for sex crimes involving children.

Police also wanted to search each of the 600 homes along the route that Shannon would normally have taken between Westmoor Junior School, where she was last seen, and her red-brick council home. A further 2,800 addresses lie within a half-mile radius of the child’s home.

Against that background police were also dealing with more than 2,000 tip-offs from members of the public. Some were crank calls, some of malicious intent and some were genuine, but often far too vague.

Police sources have dismissed at least one of the claimed tip-offs about Mr Donovan and his Lidgate Gardens flat as a fabrication. Another, in which Melvyn Glew, a neighbour, telephoned the charity Missing People, which passed on his information to the police, is said to have been too vague to justify immediate attention. Police sources told The Times that the only details they logged were that there was “a unnamed weirdo” at number 24 or 26 Lidgate Gardens and that the police ought to check him out.

An earlier tip, passing on suspicions about Mr Donovan’s overfamiliar behaviour with Shannon at a family funeral six weeks before her disappearance, is said to have joined a long list of allegations passed to the police about various relatives of the child.

The Times understands that Mr Donovan featured on the list of Shannon’s extended family tree and was due to be visited at some stage of the inquiry. He suddenly moved up the list because of information that came into police hands on Friday morning in the course of detectives’ dealings with another member of Shannon’s extended family. There had been no tip-off, police have emphasised, from anyone claiming to have heard the sound of a child’s footsteps in Mr Donovan’s flat.

A source told The Times: “You’ve got to remember that we started this inquiry with nothing. Shannon had vanished without trace. No one had seen anything. We’re very pleased with the way this investigation has been conducted. We put a system in place and there was a lot of slow, methodical work, but it has led to Shannon being recovered safe and well.”

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