Alleged bomber Mr Richard Reid has told prosecutors he used a recipe from the Internet to make part of the bomb found embedded in his shoe.
The 28-year-old Londoner bought the ingredients for triacetone triperoxide (TATP) from a man in Amsterdam, where he lived until December, CNN reported.
He then boarded an American Airlines flight from Paris to Miami and tried to light the bomb concealed in his shoe but was overcome by passengers before he had a chance to blow a hole in the side of the airliner.
The TATP would have been used to light the powerful plastic explosives known as PETN which were also in his shoe.
Reid is currently being held on remand in Boston, where the pilot of the December 22 flight diverted after the bomb scare.
He is on suicide watch and faces a 20 year sentence if found guilty of interfering with air crew - although more serious charges may be filed by the FBI.
Today CNN reported he has told authorities he found the recipe for the powerful explosive on the Internet and met a Czechoslovakian man in Amsterdam to buy the ingredients for £1,050.