The number of convictions for carrying a knife has more than doubled in a decade across West Mercia, figures reveal today.

They show that prosecutions have risen by 163 per cent – from 38 in 1998 to 100 in 2007 – across the force area, which includes Shropshire. Nationally, the number of convictions for carrying a knife has risen by half since 1998, when there were 3,805 successful prosecutions.

But in 2007, the last year for which figures are available, the total hit 6,169 – a rise of more than 62 per cent.

Some police forces in England and Wales have seen the level of convictions treble.

Opposition MPs said the data exposed the true scale of the “epidemic” of knife crime which has claimed dozens of young lives in major cities over recent months.

Shadow Home Secretary Chris Grayling said: “Knife crime blights our society.

“The figures are awful for the Government as they show yet again how Labour ministers have failed to get knives off our streets.

“We have to create a real disincentive for people who carry knives and the fact that the supposed tough sentences just aren’t happening sends out all the wrong messages.

“The Government also needs to stop wrapping up our police in unnecessary paperwork and get more officers back on to the streets,” he added.

Liberal Democrat home affairs spokesman Chris Huhne said: “These figures highlight the knife crime epidemic sweeping the country.

“However, they are only the tip of the iceberg.

“Labour’s continuing quest to sound tougher than the Tories is doing nothing to get knives off our streets.

“The key to stopping knife crime is to increase the likelihood of being caught, through intelligence-led stop and search and hotspot policing.”

The Home Office launched its Tackling Knives Action Programme (TKAP) in 10 police forces in July last year – including the West Midlands.

The aim was to try to stop the carrying of knives and reduce the number of stabbings and murders among 13 to 19 year olds.

The length of sentences handed to people found in possession of knives and other offensive weapons in England and Wales was also increased.

The £7 million programme saw the introduction of a number of new measures.

These included 1,150 extra search arches and wands, anti-knife advertising campaigns, an increase in the number of hospitals sharing accident and emergency data, and school patrols.