Commuters, survivors and families of the victims have marked the third anniversary of the 7/7 London bombings.

Hundreds of people crowded into King's Cross station to remember the 52 innocent people who were killed when four blasts ripped through London's public transport network.

London mayor Boris Johnson joined Tessa Jowell, the Government minister for the capital, and transport chiefs at the ceremony.

They laid flowers outside the station at 8.50am, the time when the first three bombs went off.

Mr Johnson laid a memorial card which said: "We honour the memory of those who died on 7/7 2005, we salute the courage of those who were injured and our thoughts and prayers are with all victims and their families."

The pavements around King's Cross, from where the four suicide bombers set off on their terror campaign, were crammed with commuters as passers-by stopped to pay their respects.

Relatives of victims and survivors also made personal pilgrimages to the sites of the four blasts - Russell Square, Aldgate and Edgware Road Tube stations, and Tavistock Square.

Many of those caught up in the bombings did not want to talk about the anniversary, saying they were trying to put what happened behind them.

Daniel Obachike, 34, from Finsbury Park, attended the King's Cross event to pay tribute to his best friend, Christian Njoya Diawara Small, who died in the blast.

He said: "It was a low-key ceremony and there are many of us who believe more could have been done in the aftermath."

He added: "I suppose it is of some consolation that figureheads have arrived to recognise us. I was with Christian the morning before he died - and obviously today feels particularly poignant."

Survivor Jacqui Putnam, 57, said: "I return every year to lay flowers. It's very important for me to be here. I don't want to be anywhere else on the 7th. The other people here today have become friends since."

Tim Coulson, 53, was awarded a medal by the Royal Humane Society earlier this year in recognition of his bravery on July 7.

He said: "My eastbound train stopped parallel to the attacked track because of the blast. I broke a window to get out of the train to get to the cries of human suffering."

Mr Coulson added: "I felt motivated to do what I could. As a teacher, all I had was a first aid certificate. I was there for the end of a life of one passenger. It was important for me for the family to know that he had not died alone because no one should."

Suicide bombers Mohammad Sidique Khan, 30, Shehzad Tanweer, 22, Hasib Hussain, 18, and Jermaine Lindsay, 19, met at Luton station on the morning of the attacks.

They took a train to King's Cross, then hugged and separated to carry out their deadly missions.

Within three minutes of 8.50am, Tanweer detonated his bomb at Liverpool Street, Khan set his device off at Edgware Road and Lindsay blew himself up between King's Cross and Russell Square.

Hussain detonated his device onboard the number 30 bus at Tavistock Square at 9.47am.

As well as killing themselves and 52 others, the bombers injured over 700 people.

Concerns have been raised about delays in paying compensation to victims of the atrocities - which Mr Johnson has described as "unacceptable".

Three years on from the bombings, 73 out of a total of 647 claims are still ongoing and some of those injured have not received any money at all.

Some survivors have complained that the compensation system is overly bureaucratic and too slow in providing for their immediate needs.

Mr Johnson wrote to Ms Jowell calling on the Government to tackle the backlog immediately.

The Criminal Injuries Compensation Authority (CICA) said it had paid out nearly £7.5 million to victims and relatives of those caught up in the bombings.

Some 89 per cent of the claims have been fully resolved and 96 per cent of those eligible have received either a full or interim payment.

A CICA spokesman said: "While we aimed to resolve all these applications as soon as possible, in some cases we still need information from third parties, for example, the police, medical specialists and employers."

The Government's assessment of the terrorism threat level to the UK remains "severe", meaning an attack is "highly likely".

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