Two men who carried out last year's July 7th attacks on London were watched by British security services but had not been viewed as urgent threats, a parliamentary committee reported today.
Mohammad Sidique Khan and Shehzad Tanweer were among four British Muslims who set off bombs on three underground trains and a double-decker bus, killing 52 people and wounding more than 700.
The intelligence and security committee said Britain's Security Service - commonly known as MI5 - had come across the pair "on the peripheries of other surveillance and investigative operations".
"At that time, their identities were unknown to the Security Service and there was no appreciation of their subsequent significance," the committee's report into the attacks said.
"As there were more pressing priorities at the time, including the need to disrupt known plans to attack the UK, it was decided not to investigate them further or seek to identify them," the report said.
"In light of the other priority investigations being conducted and the limitations on Security Service resources, the decisions not to give greater investigative priority to these two individuals were understandable," the report concluded.