Abu Qatada is accused by Britain of links with Zacarias Moussaoui, the only person charged in the United States over the Sept. 11, 2001, terrorist attacks, and with shoe bomber Richard Reid. Audio recordings of some of the cleric's sermons were found in an apartment in Hamburg, Germany, used by some of the Sept. 11 hijackers.
Authorities first tried to deport Abu Qatada in 2001, then detained him in 2002 under anti-terrorism laws, which at the time allowed suspected terrorists to be jailed without charge.
Though he was released in 2005 when the unpopular law was overturned, the cleric was kept under close surveillance and detained in various ways. He most recently was being held at London's Belmarsh prison after breaching a bail condition in March which restricted the use of mobile phones and communication devices.
The British home secretary acknowledged the delays in the legal process in her statement announcing that "at last" Abu Qatada had been deported, saying it is "clear that we need to make sense of our human rights laws and remove the many layers of appeals available to foreign nationals we want to deport."