The weapons, which are used in the United States to knock down potentially violent people without causing serious harm, are being considered by the Metropolitan Police because of a rise in the number of knife attacks on officers.
A committee has been formed to examine alternative weapons and tactics. The initiative was prompted by the death last year of PC Nina Mackay, who was stabbed trying to arrest a mentally disturbed man in breach of bail.
Among two ideas to be examined are guns that fire either a soft polyurethane "jelly" round or a special heavy cloth bean bag filled with metal shot. The projectiles, which are considered safer versions of rubber bullets, have a range of up to 80 metres and the capability to knock down a person down.
Jelly rounds can be fired from a special six-shot semi- automatic rifle, while the bean bag rounds can be fired from an ordinary shotgun.
The use of non-lethal weapons has grown in the United States after a public outcry against the number of people being shot and the rise in civillitigation against the police.
Inspector Gary Crump of the firearms policy unit at Scotland Yard said: "Our review comes partly because of a rise in the number of armed response vehicles being sent to incidents involving knives. At the moment, there are two extremes; officers with batons and CS spray at one end and armed officers at the other - there is a gap between them."
Any new non-lethal weapons will first need to be approved by the Home Office and will require vigorous testing.Reuse content