The government is considering plans to give tougher sentences to "middle men," gun runners who supply the firearms used in murders.

Home Secretary Theresa May said the "middle men are as responsible as those who pull the trigger", as she announced a consultation on the issue on Wednesday.

It follows concerns from police chiefs and politicians that current sentences of up to 10 years are too lenient.

"We need to target not just those who use illegal firearms but those who import or supply them," May said.

"These middle men are as responsible as those who pull the trigger for the terrible harm gun crime causes.

"We must ensure our laws properly punish and deter all criminals and protect our communities."

The Association of Chief Police Officers (Acpo) said there were only a small number of guns in circulation which were traded between gangs and used in a series of attacks

The government is looking at whether a new offence of possession of illegal firearms with intent to supply is needed and whether the maximum sentence for illegally importing firearms should be increased.

"The UK has some of the toughest gun laws in the world and as a result firearm offences continue to make up a small proportion of overall recorded crime.

"However, gun crime associated with street gangs and organised criminals, particularly in our largest cities, is a cause of major concern with young people featuring disproportionately among both perpetrators and victims," the Home Office said.

Under the current laws, offenders face a maximum of 10 years in prison for either the "supply" or "possession" of firearms, and for illegally importing firearms or ammunition.

But there is no offence of "possession with intent to supply" firearms.

Young people aged 15 to 29 make up just a fifth of the population but were victims in nearly half (45%) of firearms offences in 2010/11, figures show.