GUN runners who sold and supplied weapons to drug gangs have been jailed for 54 years.

Dangerous ringleaders Paul Alexander and Carl Gordan, who were already serving life sentences in jail, managed to maintain their sophisticated criminal network despite being behind bars.

They used illegal mobile phones to organise the legal purchase of obsolete firearms which were then converted and made alive, and therefore illegal.

Alexander then passed on his knowledge about converting ammunition to others including his family in Harwich.

Questions will be asked about how they were able to continue their lives of crime from inside prison cells.

Police first became aware of what was happening in 2011 with 12 guns seized and defendants sentenced to 28 years.

On Friday, at Woolwich Crown Court, seven were sentenced.

Among them were Alexander, 58, who admitted conspiracy to supply firearms with intent to endanger life.

He was sentenced to 16 years, to be served after his current prison sentence ends in 2015.

His wife, Caroline Hunter-Mann-Purdy, 64, of Harwich Road, Harwich pleaded guilty to conspiracy to supply firearms and was sentenced to seven years.

Alexander’s step-daughter, Lullabell Purdy, 26, of Harwich Road, Harwich pleaded guilty to money laundering offences and was sentenced to 300 hours of community service.

Det Insp Richard Mills said: “During the period that Gordon and Alexander met in prison, they effectively became business partners, dealing in deadly weapons and ammunition.

"The firearms and ammunition they converted had the potential to cause great harm on our streets.

“This was a complex investigation by the Met’s Special Intelligence Section, which is committed to targeting criminal networks and bringing a successful prosecution.

"I would like to pay tribute to the detectives who have worked tirelessly to see this case to its successful conclusion.”

Alexander was in jail after a gun factory was discovered at his rented home in Bardfield Saling in 2008.