London was grayer than usual Tuesday as it marked the 10th anniversary of the worst terrorist attack in recent British history. On July 7, 2005, bombers linked to al Qaeda set off explosions on three London Underground trains and one bus. The explosions killed 52 people and injured more than 700.
Survivors and victims' families attended a memorial service Tuesday at St. Paul's Cathedral in London, the BBC reported. The tribute culminated with a moment of silence, petals falling from the church's dome and four lit candles representing the bombing sites.
During the bombings, St. Paul's dome symbolized Londoners' unity, so it naturally became the message of the service.
"Beyond the numbing shock of what happened, there was solidarity. There was unity in our grieving," Richard Chartres, the Anglican bishop of London, said in his address.