Revealed: The double lives of Yorkshire’s July 7 bombers

Two of them were fathers of young children whose partners were pregnant at the time of the atrocities.

And two of the terrorists started secret relationships just before the suicide attacks, with one even trying to arrange to spend his last night alive in a London hotel with his new girlfriend.

But in general their behaviour around their loved ones was chillingly normal as they hatched their murderous plans.

• Mohammed Sidique Khan, who killed six people at Edgware Road on the Circle Line

The ringleader, recruiting sergeant and main financier of the 7/7 plot grew up in the deprived Beeston area of Leeds.

Khan, 30, appeared to be a pillar of the community, steering local youths away from crime and drugs by organising outdoor activities and helping to set up a gym in a mosque basement.

In 2001 he became a learning mentor at Hillside Primary School in Beeston, where he worked with disaffected and vulnerable pupils with behavioural problems.

He was highly respected by the teachers and young people who knew him, with some children from single-parent families regarding him as a “father figure”.

But Khan abused his position, befriending one Hillside pupil aged 11 or 12 and attempting to radicalise him by claiming people would “pay” for what they had done to Pakistan.

The bomber’s own path to extremism began with flirtation with hardline Islamist group al-Muhajiroun, linked to hate preacher Abu Hamza, and continued with trips to jihadist training camps in Pakistan and Afghanistan.

He also had brushes with British police in 1986, when he was arrested aged just 11 for receiving stolen goods, and 1993, when he received a caution for an assault committed the previous Boxing Day.

Khan married Hasina Patel in October 2001 and they had a daughter in May 2004. His wife became pregnant again but learned she had suffered a miscarriage on the morning of the London bombings.

The terrorist returned to Pakistan in November 2004 having made a home video in which he said goodbye to his baby daughter forever, seemingly because he was planning to die fighting.

But there was a change of plan and he returned home, apparently having been ordered by a senior jihadist to carry out an attack in Britain.

Police believe that in the weeks before the bombings he received bomb-making instructions in a series of phone calls from a mysterious backer in Rawalpindi, Pakistan.

Before killing himself and six innocent people, Khan left a will in which he apologised to his wife for lying to her and said leaving his baby daughter behind was “the most difficult thing in my life”.

• Shehzad Tanweer, who killed seven people at Aldgate on the Circle Line

Tanweer was Khan’s right-hand man in planning and executing the London bombings.

Outwardly he seemed thoroughly assimilated into British life, working in his father’s fish and chip shop and regularly playing cricket, but he underwent a transformation after the 9/11 attacks on the United States.

Tanweer, 22, came from a relatively well-off family in Beeston and excelled both in his school work and on the sports field.

He lived near Khan and became friends with him in 1999 when he was about 17.

By 2004 the pair were jointly involved in Islamist extremism. They made long round trips to meet British terrorists plotting a fertiliser bomb attack and travelled to Pakistan together at the end of that year.

Tanweer too had a minor criminal record. He was arrested on suspicion of burglary but not charged in 1995 and received a caution for a public order offence in 2004.

In the weeks before the London attacks friends noticed orange streaks in his hair - apparently caused by the peroxide he was using to make the bombs - but otherwise there were no signs of what he was planning.

In early 2005 Tanweer reignited a relationship with a woman he had secretly been involved with some years before, and he spent a night in a hotel with her six days before he carried out his appalling mission.

On the evening before he murdered seven fellow passengers on a Circle Line train, his family recalled that he played cricket and his only worry seemed to be that he had lost his mobile phone.

• Jermaine Lindsay, who killed 26 people between King’s Cross and Russell Square on the Piccadilly line

The wild card among the four bombers, Lindsay was a Jamaican-born Muslim convert who never made a secret of his extremist views.

He was brought up by his mother in Huddersfield, where he alarmed his teachers by attempting to radicalise impressionable younger pupils.

Lindsay, 19, handed out leaflets in support of al Qaida and Osama bin Laden and downloaded inflammatory material about the Taliban and the 9/11 attacks in the school library.

He told one teacher he wanted to fight in Afghanistan and even boasted of planning to join the British Army so he could kill his fellow soldiers.

Lindsay met his future wife, Samantha Lewthwaite, in an internet chat room before they got together face-to-face at a Stop The War march in London.

They married in October 2002, moved to Aylesbury, Buckinghamshire, in September 2003, and had a son in April 2004. Ms Lewthwaite was expecting again when he killed himself.

His wife reported that his behaviour changed after he became close to Khan in late 2004, and on one occasion he assaulted her.

Lindsay was the only one of the bombers who did not have a criminal record, but his car was linked to a suspected armed robbery in Luton in May 2005 which could not be fully investigated.

Despite having a heavily pregnant wife, he started a relationship with a 17-year-old girl called Nicki Blackmore just over a fortnight ahead of the bombings.

Lindsay asked Miss Blackmore to get him a gun because he had to “teach some people a lesson” in London, and begged her - unsuccessfully - to spend the night before the attacks with him in a hotel in the capital.

In another sign of his strange mental state, Lindsay exchanged jokey text messages with Khan on the eve of their suicide missions in which the two bombers posed as characters from cult 1980s TV drama The A-Team.

He carried out the deadliest of the attacks, killing 26 people on a Piccadilly Line train packed with commuters trying to get to work after earlier disruption on the line.

• Hasib Hussain, who killed 13 people on a number 30 bus in Tavistock Square

The youngest member of the terror cell had a final chance to abandon the plot, but instead found an even more obscene way of murdering innocent Londoners.

Hussain, 18, was an unexceptional teenager who had an ordinary upbringing in the Holbeck area of Leeds.

He raised concern among his teachers when shortly after the 9/11 attacks he passed two fellow pupils a note which said, “You’re next” in a reference to the terrorist atrocities in the US.

The future bomber also defaced a religious education schoolbook with the slogan “Al Qaida No Limits” and a picture of planes crashing into the World Trade Centre in New York when he was just 15 or 16.

Hussain met Khan in around 2001 through a mosque in Beeston and became visibly more religious after carrying out the Hajj pilgrimage to Saudi Arabia with his family in early 2002.

He received a caution for shoplifting in October 2004 after trying to steal a hat and a pair of gloves.

After the attacks police were able to track Hussain’s movements on July 7 2005 in great detail thanks to painstaking analysis of CCTV footage.

He was captured on camera emerging from the Tube at King’s Cross station and joining the melee of commuters evacuated after the three initial blasts at about 8.50am.

After attempting to phone his fellow bombers, he bought a £4.49 replacement nine-volt battery for his device’s detonation circuit from a WH Smith store in the station.

The teenager inserted the new battery into his bomb in a nearby branch of McDonald’s before boarding a number 91 bus, where other passengers noted that he was sweating profusely and looked like a lost tourist.

The bus terminated early and Hussain got on a number 30 red double-decker bus. He took a seat at the rear of the top deck and waited until the vehicle was in Tavistock Square before blowing himself up and killing 13 people.