In response to Graham Burgess (Letters, May 31), it is now an offence under the Anti Social Behaviour Act 2003 to manufacture, sell, purchase, transfer or acquire an air weapon that uses a self-contained gas cartridge system.

Anyone holding this type of weapon had until April 30 this year to apply for a Firearms Certificate or to hand it in. This was widely publicised locally and Sussex Police issued 127 firearms certificates, covering 385 weapons, from applications received before the closing date.

New certificates cannot be issued for applications received after 30 April, so anyone now in possession of this type of air weapon without a firearms certificate is committing an offence which may result in a minimum of five years imprisonment.

Many such weapons may now be illegally held. Offenders should seriously consider their position.

Sussex Police will deal sympathetically with anyone who finds they are contravening the law, as long as they take the weapons to a police station.

-Rodney F Ash AIExpE, Firearms and explosives licensing branch manager, Sussex Police, Lewes