On the face of it, it appears that there might not be an urgent need in Bradford for metal-detecting devices to be installed to seek out knives being carried by pupils, as is being planned for hundreds of schools across the country. Apparently only three knives were confiscated from youngsters in the district during 2006/07, plus a catapult and stone and a ball-bearing gun.

If that is the true scale of the problem in Bradford, perhaps we should consider ourselves very lucky. But were those three knives merely the tip of the iceberg? Were they the only ones confiscated because others escaped detection?

Teaching union officials believe that to be the case. Pam Milner, Bradford branch secretary for NASUWT, claims there are many more pupils in Bradford who have weapons stashed near school or in school. She says that bringing back bag searches and introducing airport-style scanning is a way of tackling the problem.

In fact, although the total of three knives and two other weapons detected is relatively small given the number of pupils in Bradford's school system, it is likely that those fears of a bigger, hidden problem are justified to some extent. School staff need to be increasingly vigilant if we are to discover whether or not this is a big issue in Bradford.

If it is found to be the case, then any schools where knives are found to be a problem should volunteer for the detection programme in a bid to head off the rise in violent crime among the district's youngsters that has already been seen elsewhere.