A man accused of conspiring to bomb London's public transport system told a court Monday that he learned how to make explosives from the Internet, but deliberately made fake devices that would spread fear and panic in a protest against the invasion of Iraq. Muktar Said Ibrahim, 29, said that eight months before the attacks he downloaded a Web video on which an Arabic-speaking man in a ski mask described how to make explosives from hydrogen peroxide, an easily obtained household chemical. "When I saw how easy it is to make the stuff, the idea came to my head that I could use it to make fake explosives," Ibrahim told jurors at London's Woolwich Crown Court. "If you know how to make it work, you can make it to not work." Ibrahim and five other men are being tried on charges of conspiring to bomb the British capital's transport system on July 21, 2005, two weeks after four suicide bombers killed themselves and 52 bus and subway passengers. Prosecutors say the July 21 plot failed only because the four bombs, carried onto three subway trains and a bus, failed to explode. Ibrahim; Yassin Omar, 27; Adel Yahya, 24; Manfu Asiedu, 33; Hussain Osman, 28; and Ramzi Mohamed, 25, all deny conspiracy to murder and conspiracy to cause explosions.