Police are trying to trace a gang of British Muslims who are thought to have returned to plot terror attacks in Britain after being trained abroad for more than a year by al-Qaeda, Nine Britons, all said to be in their twenties, were among a group of 12 Western recruits groomed by al-Qaeda at a secret camp near the Afghan border to set up new terror cells in London and other Western capitals. Police do not know the real identities of this gang, who are known as the “English brothers” because of their shared language. As well as nine Britons,...