A former anti-terrorism chief has called for an independent public inquiry into how the suicide bombers were able to carry out the July 7, 2005 attacks.

Andy Hayman, who was Assistant Commissioner for Special Operations at Scotland Yard at the time, said without an open inquiry "no one can be sure if key issues have been missed".

His comments - made in his book, The Terrorist Hunters - come almost four years on from the terror attacks when four bombs ripped through London's public transport network, killing 52 people.

He said: "Incidents of less gravity have attracted the status of a public inquiry - train crashes, a death in custody, and even other terrorist attacks. How can there not be a full, independent public inquiry into the deaths of 52 commuters on London's transport system?

"There has been no overview, no pulling together of each strand of review, no one can be sure if key issues have been missed."

Mr Hayman said he is "uncomfortable" with the official position that an inquiry would divert resources from the fight against terrorism.

Survivors and relatives of the July 7 victims have taken their fight for a public inquiry to the High Court following last month's publication of a report by the Intelligence and Security Committee (ISC).

The report exonerated the security services of any blame for leaving Mohammed Sidique Khan, the mastermind behind the July 7 attacks, free to plot the bombings.

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