Inquests have begun into the deaths of 52 people killed in the 2005 London bombings.
The inquests had been delayed due to questions over what exactly they should cover and because of criminal investigations into the bombings.
Coroner Lady Justice Hallett will examine whether MI5 could have intercepted the bombers before the attacks on three packed trains on the Underground and a bus.
However, but many victims families have been calling for a public inquiry.
As well as the 52 people killed, about 700 people were wounded, some permanently.
The hearings at the Royal Courts of Justice in London are expected to last until at least March 2011 and will look at exactly what happened in the run-up to the attacks.
The attacks were the work of four al-Qaeda suicide bombers who were all British nationals.
Since the 7/7 attacks, it has emerged that the ringleader and one of the other bombers were known to homeland security police.