MORE than half of all the UK’s dogs specially trained to find missing people are now on the Shannon Matthews investigation, the biggest search of its kind ever in West Yorkshire.

Police teams from across the country are in Dewsbury, hunting for the timid nine-year-old who vanished three weeks ago.

Dogs have been drafted in from Strathclyde in Scotland, Surrey, Hampshire and Greater Manchester to help the West Yorkshire dogs.

The operation continues at full pace, with more than 300 officers working on the baffling case as they continue to search 3,000 homes and businesses in the Dewsbury Moor area.

The dogs can sniff out people who are alive and in trouble – possibly after a fall – but can also find decomposing bodies and blood.

Detectives continue to hope they will find Shannon alive, but continue to “consider every possibility”.

Chief Insp Graham Armitage, who is in charge of the search part of the hunt for Shannon, said 16 of the UK’s 27 specialist victim recovery dogs were now involved in the search, both in homes and outside.

He said handlers were working up to 14-hour days to maintain the momentum.

“The dogs are trained to find anything from live human beings to traces of blood,” he added.

Asked if the dogs had actually found anything he replied: “We’ve had a number of indications.

“But obviously dogs will indicate on a simple nosebleed and this is completely innocent. So we have had a number of indications, all of which have been investigated.”

He added: “We are hoping we will find Shannon alive and well, but have to consider every possibility.”

Chief Insp Armitage revealed details of the search during a press briefing yesterday in Crow Nest Park, about a mile and a half from Shannon’s home in Moorside Road, Dewsbury Moor.

He said: “There is a massive amount of resources committed here. It is a huge operation.

“Every individual here is committed to finding Shannon. The officers are still very well motivated. This is the biggest missing person inquiry I’ve been involved in over my 28-year service.”

Asked whether the search would extend beyond Dewsbury and the immediate area he said the operation could only be guided by information it was given.

“It’s all about information,” he said. “When we get that information we go where it takes us.”

He confirmed that some of the landmark outdoor areas already thoroughly searched include Crow Nest Park, Spen Valley Greenway and Jessop Park in Batley, along with allotments and playing fields.

Det Supt Andy Brennan, who is leading the overall search for Shannon, said the last confirmed sighting of her remained at 3.10pm on February 19.

The shy youngster was seen by teachers leaving Westmoor Junior School following a swimming trip.

Since then West Yorkshire Police have mounted an operation involving 250 officers plus a team of 60 detectives.

Chief Supt Brennan repeated his statement that he is gravely concerned for Shannon.

He said officers were now about two-thirds of the way through a list of 3,000 homes and commercial premises which were being searched.

He said the concentration of this effort remained on the route Shannon should have taken home from school.

Chief Supt Brennan said: “Clearly, in the first couple of days we were looking to recover Shannon at the earliest opportunity.

“We then restructured the searches to review all the search areas and look for anything that might be evidence.

“That type of search is far more detailed than just searching for Shannon herself.”

Last night Shannon’s family and friends were joined by many people from Dewsbury for a sponsored walk to mark three weeks since she vanished and raise money for their continuing search efforts.

The Sun newspaper has increased the reward it is offering to help find Shannon from £20,000 to £50,000.