original tip-off about the alleged plot came more than a year ago

Police officers outside the Masjid-E-Umer mosque in Walthamstow. Photograph: Toby Melville/Reuters
Guardian Unlimited | Special reports | Terror plot: Pakistan and al-Qaida links revealed

British intelligence sources say the original tip-off about the alleged plot came more than a year ago from an informant in the UK. The informant is believed to have come from the Muslim community.

Although some had visited Pakistan, a senior security official said:
"The plot was constructed in the UK, targeted in the UK, based in the
UK, and foiled in the UK"

• .But it is not clear when the attack was to take place. None of the
  alleged plotters had yet bought airline tickets, according to
  anti-terrorist sources.