TIMELINE - Events surrounding the 21/7 attacks

LONDON (Reuters) - Here is a chronology of the events leading up to and following the July 21 attacks.

May 2004: Five of the men -- all except Asiedu -- were watched by police surveillance officers at a camp site in the Lake District.

December 2004: Ibrahim travelled to Pakistan and returned to Britain in March. Serious planning for the attacks started soon after, police say.

April 27 - July 5, 2005: The men buy 442 litres of hydrogen peroxide which they concentrated to form bombs.

June, 2005: Yahya leaves Britain for Ethiopia.

July 7: Four suicide bomb blasts on London transport during the morning rush hour kill 52 people and injure about 700. The bombs explode on three underground trains and a double-decker bus.

July 21: Four of the men attempt to carry out a second wave of attacks on three London underground stations and one bus, mimicking the 7/7 bombings.

- Asiedu told the court he dumped a fifth bomb in a park in northwest London.

July 22: Police mistakenly shoot dead Brazilian electrician Jean Charles de Menezes at London's Stockwell underground station, believing he is one of the would-be suicide bombers.