Three Asian-origin men were being questioned by British police on Friday after being arrested in connection with the 7/7 suicide bombings in London that killed 52 people.
Two men, aged 23 and 30, were arrested on Thursday at Manchester Airport when they were due to board a flight to Pakistan. A third suspect, aged 26, was held in Leeds.
Scotland Yard sources said the three men, all of Asian origin, are suspected 'backroom boys' who could have provided help and support for the four suicide bombers.
They are being held on suspicion of the commission, preparation, or instigation of acts of terrorism.
Fifty-two people died in July 7, 2005 after four suicide bombers attacked three London Underground trains and a bus. The four bombers died in the explosions, and no-one has yet been charged over the
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