Britain fell silent at noon for two minutes to mark the first anniversary of the London bombings that claimed 52 lives and injured hundreds.

The silence is one of the events taking place to commemorate the 7 July suicide attacks on the capital.

Flowers were laid at the sites where bombs went off on three Tube trains and a bus at the times of the blasts.

Tony Blair said the anniversary of the attacks was an opportunity for "the whole nation to come together".

A public ceremony with readings will be held later in Regent's Park.

The two-minute silence was being observed across the country, including the Wimbledon tennis championships and at other events.

The commemoration comes as Metropolitan Police Commissioner Sir Ian Blair gave a firm warning London must expect another attack.

"I know there will be further attacks, but as to whether we will stop those, well we've stopped three already," Sir Ian told BBC News.

And Colin Cramphorn, chief constable of the West Yorkshire force said he believed other 7 July-style attacks in the UK were "not just fanciful" but "very possible".

On Thursday, a video of one of the bombers, Shehzad Tanweer, was aired on al-Jazeera television. It showed the 22-year-old, from Leeds, warning of further attacks.

Private events

Members of the public have been laying purple carnations within a floral mosaic in Queen Mary's Gardens, Regent's Park.

Later, survivors and the bereaved will complete the centre of the mosaic with yellow gerberas, and the public can pay their respects over the weekend.

Mr Livingstone was joined by Culture Secretary Tessa Jowell in laying flowers at King's Cross station - which became a main focus for tributes in the aftermath of the attacks - at the exact time of the Underground bombings.

Mr Livingstone told the BBC News website Friday was a time to remember those individuals whose lives had been ruined by the attack.

It was also and a time to be proud of London's unique character, which had been a source of envy to the bombers, he said.

Ms Jowell said the government would not be granting the wishes of many relatives to hold a public inquiry into the events.

She said an inquiry would mean an "enormous diversion of security resources which need to be directed to preventing this happening again".

Richard Innishannon - one of the first on the scene at the Tavistock Square bus bombing - was among those gathered at King's Cross.

He said he has been so traumatised by what he saw a year ago that he has only been on a train once since.

"My stomach is in knots but I don't live that far from here and I just felt that I had to be here today."

Memorial plaques

The bells of London's St Paul's Cathedral tolled at 0850 BST to mark a year since the bombs went off on trains near Aldgate and Edgware Road stations, and on another travelling between King's Cross and Russell Square.

They also tolled an hour later to mark the fourth blast on the number 30 double-decker bus at the junction of Tavistock Square and Upper Woburn place.

Other events on Friday will be held in private for victims' families and survivors.

Memorial plaques at King's Cross, Russell Square, Edgware Road, Aldgate and Tavistock Square were unveiled.

A Book of Tributes, with a foreword from the Prince of Wales and tributes from the bereaved, will also be unveiled in a private event.

Commuters across the capital have seen a high-visibility police presence on the transport network.

The 7 July Assistance Centre can be contacted on 0845 054 7444.

Source: BBC

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