SCOTLAND Yard came across one of the alleged July 21 bomb plotters three times in the months before he tried to detonate a shrapnel-packed rucksack bomb on a London bus, a court heard.
Muktar Said Ibrahim was photographed by Metropolitan Police surveillance officers at a camping trip in the Lake District, along with four of his alleged co-conspirators, almost 15 months before their attempted suicide attacks, their trial at Woolwich Crown Court was told.
A few months later Ibrahim was arrested outside the Debenhams store on London's busy Oxford Street for distributing 'Islamic literature'.
Then in December, 2004, he was questioned by Special Branch at Heathrow airport, while on his way to Islamabad in Pakistan, the court heard.
When searched, Ibrahim - who said he was unemployed but worked as a market trader - was found to be carrying more than £2,000 and a new video camera and video phone.
He was also carrying a sleeping bag, cold weather clothes and anti-malarial tablets, the jury was told.
Soon after he returned to Britain in early 2005 he and his alleged co-conspirators began preparing to bring death and carnage to the travelling public, the prosecution says.
Ibrahim, 28, of Stoke Newington, north London, is one of six men accused of hatching an extremist Muslim plot to carry out a series of murderous suicide bombings on London's public transport system on July 21, 2005, two weeks after the July 7 bombings killed dozens in the capital.
He allegedly tried to blow up a homemade explosive mixture of hydrogen peroxide and chapatti flour on a bus on Hackney Road in east London.
The other defendants are Ramzi Mohammed, 25, Yassin Omar, 26, Hussain Osman, 28, Manfo Kwaku Asiedu, 33, and Adel Yahya, 24.
The trial continues.