Nick de Bois is a former MP for Enfield North.

Yet another teenager – this time 16-year-old Mohammed Kwenga – fell victim to London’s knife crime crisis this week. Already this year, ten teenagers have been killed by knives, compared to eight last year.

There is clear evidence that the use of knives on the streets of London is on the increase, with injuries as well as deaths on a steady incline. It’s simply not clear why, after six years of constant decline, assaults and murders appear to be on an upward trend.

Last week, during an evidence session at the London Assembly’s Police and Crime Committee, the Metropolitan Police suggested this could, in part, be related to the reduction of the use of stop and search in London. There were also suggestions that the availability of knives on the internet is having an impact, as well as the fact that previously imprisoned offenders are now returning to the streets.

What is clear is that nobody actually knows for sure. This isn’t good enough.

When it comes to tackling gang and knife crime – especially stabbings and murders, the most important factor to consider is that for an individual to kill someone with a knife, he has first to decide to carry a knife.

Young people are continuing to get caught up in knife crime, which is significant evidence of the prevalence of gangs on our streets. The average age of offenders doesn’t increase year on year, which implies there is a continuing stream of young people who aspire to join gangs and readily become involved in knife crime.

This endless supply of youngsters, combined with the toxic mix of easy available knives and the constant changes in enforcement strategies, creates a deadly mix. These things can be tackled, but it isn’t simple.

When I helped to introduce laws, while a Member of Parliament, to ensure that anyone convicted of carrying a knife for the second time was sent to jail, I did it so in the knowledge that multiple offenders were currently “getting away with it”. They experienced no consequences for their actions; their behaviour was allowed to continue almost entirely unchallenged.

It was clear that introducing tougher sentencing was only a part of the solution. Reducing knife crime requires an holistic approach in which prevention and early intervention is as important as punishment. Currently, poorly funded volunteer groups who aren’t reliant upon state support – such as the Ben Kinsella Trust and Only Cowards Carry – lead the way in showing what can be achieved.

Inevitably, however clear their results are, the impact they have is limited by how extensively they and others can practice their skills.

The heavy hand of state bureaucracy, complex bidding processes and sometimes local government inertia frustrate the voluntary sector. Government, at local and national level, needs to fill the vacuum of leadership on this, and champion early intervention and prevention across London and the UK. It is not good enough to rely on tough sentencing laws without empowering the voluntary organisations who can reach out to those vulnerable to the perverse gang and knife culture.

It is time to put gangs and knife crime back on the political and public agenda – and, above all else, put early intervention and prevention at the forefront of how we tackle it.