The Hatton Garden ringleader known as “Basil” has been found guilty four years after carrying out the £14m heist.

Michael Seed, 58, an alarm specialist, is believed to have let himself into the safe deposit facility in London using a set of keys before disabling the security system.

He was one of two men who climbed into the vault to loot 73 deposit boxes after a gang of criminals drilled through a thick concrete wall over the 2015 Easter bank holiday weekend.

Seed, who pays no taxes, claims no benefits and rarely uses a bank account, evaded capture for three years before police raided his flat in Islington, north London, on 27 March last year.

The electronics expert told a jury at Woolwich crown court he was not the man nicknamed “Basil” by the rest of the gang.

But on Friday, he became the 10th person convicted in connection with the crime when was found guilty of conspiracy to burgle the Hatton Garden Safe Deposit Company and conspiracy to handle the proceeds, after gold ingots, gems and jewellery worth £143,000 were found in his bedroom.

Seed was cleared of conspiracy to burgle the Chatila jewellery store in Bond Street over the August bank holiday weekend in 2010 with members of the same gang.

Prosecutors had alleged he posed as a BT engineer to tamper with the security system before the burglary, then used a 2G mobile phone jammer to block the alarm signal.

The thieves failed to drill into a safe containing £40m in gems, but made off with jewellery worth £1m from display cabinets.

The jury of six men and six women deliberated for 35 hours and 35 minutes before returning their verdicts on Friday.

Seed, who grew up in Cambridge, appeared expressionless moments after the verdicts were returned. The judge, Christopher Kinch QC, said he would sentence him later on Friday.

Seed’s fellow Hatton Garden ringleaders Brian Reader, 80, John “Kenny” Collins, 78, Daniel Jones, 64, and Terry Perkins, who died in prison last year aged 69, were all jailed in 2016.

Collins and Reader have been released but face returning to jail if they fail to pay back more than £6.5m of the proceeds police believe could still be under their control.

Detectives believe the gang may have been operating undetected for decades before they were caught, but cannot link them to any other crimes.

Seed travelled abroad three times after he was first photographed meeting Collins by a surveillance team in the weeks after the Hatton Garden burglary, while unknown to police.

Philip Evans QC, prosecuting, suggested Seed, who studied electronics and physics at Nottingham University, may have taken stolen cash to Portugal, where Perkins had a holiday flat in the Algarve.

Seed was identified by the Flying Squad at the end of November 2015 and further surveillance footage showed him walking around Canary Wharf in April 2016.

But detectives waited until until March last year to catch Seed with more than 1,000 items stolen in the Hatton Garden heist.

He was believed to have been melting down gold and breaking up jewellery on his bedroom workbench as it was brought in from a bigger stash.

Dr Gordon Burrow, a gait expert, compared covert footage of Seed with CCTV images of Basil, disguised in a ginger wig, facemask and hat as he carried a black bin bag to and from the scene, to obscure his face from the cameras.

He told jurors the “unusual” limp offered strong support for the prosecution case that Seed was Basil.

Prosecutors said electronic equipment found in his flat, including an alarm panel and a mobile jammer, was used for training, and suggested he may have worn a BT uniform to gain access to the buildings prior to the crimes.

Evans said: “These two offences in particular required very specialist skills and knowledge to defeat the alarms and security measures in the premises.

“The prosecution suggest that Mr Seed is one of those people and had the requisite level of skill and knowledge to assist in the successful execution of these crimes.”

Seed claimed he could have been on a family holiday in Cornwall or visiting his elderly mother in Cambridge at the time of the Hatton Garden burglary, and told jurors he had never been known as Basil.

“Everybody calls me Basil now,” he said. “I’ll be known as Basil for the rest of my life.”