Police have urged the Home Office to close a loophole which is allowing hundreds of unlicensed handguns to be brought into Britain legally.

The guns are being sold to criminals after entering Britain, an investigation has revealed.

The handguns are exempt from legislation, which requires firearm owners to have a licence because they were produced before 1939 and are old enough to qualify as antique weapons and were designed for calibres of ammunition which are now considered obsolete.

But despite this, criminals have been able to manufacture their own rounds for the guns, which have been used in six killings and dozens of shootings so far.

Some of the components used in making the ammunition can be obtained online or at weapons fairs without a licence.

The government is now facing calls to amend the law in order to stop such weapons being freely bought and sold.

Currently, only those who have served at least three months in jail are forbidden to own them.