The Prime Minister and Duke and Duchess of Edinburgh were among those who gathered to mark the 20th anniversary of the July 7 London bombings at St Paul's Cathedral.Four co-ordinated attacks on three Tube trains and a double-decker bus killed 52 people and left several hundred injured in the worst single terrorist atrocity on British soil.

The Prime Minister and Duke and Duchess of Edinburgh were among those who gathered to mark the 20th anniversary of the July 7 London bombings at St Paul's Cathedral.Four co-ordinated attacks on three Tube trains and a double-decker bus killed 52 people and left several hundred injured in the worst single terrorist atrocity on British soil.