Thugs who plan to launch knife attacks are "unlikely to surrender" the blades in any amnesty, a Lancashire MP said, as an investigation showed knife crime went up immediately after a high-profile campaign.
Blackpool North and Cleveleys MP Paul Maynard, a Conservative, spoke after this newspaper revealed there were 99 total knife crimes across the county in the two weeks after Operation Sceptre was held in March. In the two weeks before, there were 95.
But Mr Maynard insisted amnesties still have their place on the front line in the fight against knife crime.
He said: "It is clear a variety of measures are needed to reverse the rise in violent crime, including improved education, targeted policing, and operations such as knife amnesties which take weapons off our streets. I would not rule out any strategy which helps in this fight.
"It stands to reason that those who intend to use knives as offensive weapons are unlikely to surrender them in any amnesty. However, any measure which reduces their potential access to blades is of value as part of a wider package of measures.
"The best way in which to tackle knife crime is through cultural change, pressing home the message it is not safe or acceptable to carry a bladed weapon."
Operation Sceptre, described as a "week of action aimed at reducing knife crime", ran from Monday, March 11, to Friday, March 15. Knife bins were put inside police stations in Blackpool, Preston, Burnley, Morecambe, Fleetwood, Blackburn, Chorley, and Nelson, with people urged to surrender their blades no-questions-asked amid an alarming surge in violence.
Some 182 knives were said by the force to have been handed in, and were set to be melted down.
Lancashire's Police and Crime Commissioner Clive Grunshaw said he found the rise in crime after the amnesty "concerning", but said: "They do not mean campaigns here in Lancashire and across the country do not play an important role in the battle against knife crime."
The charity Centre for Crime and Justice Studies said in a recent report: "Little research exists on whether knife amnesties reduce knife crime. An assessment by the Metropolitan Police of the effects of a five-week national knife amnesty in the summer of 2006 found a marginal decrease in knife-enabled offences which lasted for eight weeks before returning to pre-amnesty levels."
Fleetwood and Lancaster's Labour MP Cat Smith, the shadow minister for youth affairs, said: "The findings of this investigation into knife crime in Lancashire is yet more evidence highlighting the devastating impact of austerity on our communities.
"The number of knife-related offences continues to soar under this government. The overstretched and under-resourced police and criminal justice systems are only able to tackle a fraction of the total level of crime."
Lancashire Police has had to make savings of £84 million since 2010, with a further £20m to find by 2023, leading to 750 fewer officers, Mr Grunshaw said.
The force has been contacted for a comment.