Now questions have been raised about the Government's knife-crime campaign and why ministers designated West Yorkshire as a knife-crime hotspot.

Some opposition politicians say it is window dressing and raised fears that police are having to divert resources from more pressing areas, like gun crime.

Metal detecting knife arches have been used during the last two weekends at nightclubs in Leeds city centre.

On August 9 and 10, 724 revellers were searched and another 1,200 last weekend.

West Yorkshire Police and British Transport Police also used knife arches to search 182 people at the bus station and 90 at the railway station in Dewsbury on August 7.

No weapons were found during any of these searches.

Knife arches will be used again in Leeds this bank holiday weekend.

Sgt Paul Maxfield, who oversaw the city centre operation last weekend, said the outcome "should reassure visitors to the city centre that Leeds does not have a significant knife crime problem".

Deputy council leader and leader of the Tory group Andrew Carter said eyebrows had been raised when the Home Office first designated West Yorkshire as a knife hot-spot. There were 915 knife crimes in West Yorkshire in 2007/08, with 7,409 such offences in London, 2,303 in West Midlands and 2,294 in Greater Manchester.

Coun Carter said: "It is window dressing. It's giving the message to the public but diverting police resources from other areas of criminal activity where they might be more required."

Council leader and leader of the Lib Dem group Richard Brett said he hoped West Yorkshire Police would "feed back to the Government whether there are better ways of spending money."

Recent knife searches also took place in Greater Manchester (2,700 searched, two arrests) and Merseyside, (3,000 searched, three arrests).

West Yorkshire Police website

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