Gas Attack in London Foiled by Scotland Yard

The Times

"SCOTLAND YARD believes it has thwarted an Al-Qaeda gas attack aimed at ministers and MPs in parliament. The plot, hatched last year, is understood to have been discovered in coded e-mails on computers seized from terror suspects in Britain and Pakistan."
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“They were planning to use chemicals, a dirty bomb and sarin gas. They looked at all sorts of ways of delivering it.”