Jury selection began Thursday in the trial of six men accused of trying to bomb London's transport network in 2005, two weeks after suicide bombers killed 52 bus and subway commuters in the city.

The six men deny charges of conspiracy to murder and conspiracy to cause explosions.

Dressed smartly in dark suits and ties, the men, most of whom are of East African descent, sat silently at the back of the courtroom, flanked by security guards, as more than 100 prospective jurors were led into court.

Judge Adrian Fulford told jurors the trial "comes after all the shock, confusion and press reporting" of attacks in July 2005. He told the prospective jurors they would be asked to decide whether the defendants intended to kill -- not whether killing was justified by any religion or ideology.

The abortive July 21, 2005, attacks on three London Underground trains and a bus shook a city reeling from the July 7 explosions that killed dozens of passengers and four bombers -- the deadliest attack on London since World War II and the first suicide bombings in Western Europe.

On July 21, devices were triggered, again on three subway trains and a double-decker bus. They failed to detonate fully, and no one was injured.

The judge said the trial of Ibrahim Muktar Said, 28, Ramzi Mohamed, 25, Yassin Omar, 26, Manfu Asiedu, 33, Adel Yahya, 24, and Hussain Osman, 28 -- all from London -- is expected to last between three and four months.

Most of the suspects were arrested in Britain a few days after the failed bombings. Osman was detained in Rome a week after the attacks.

Prospective jurors at Woolwich Crown Court, a heavily fortified courthouse next to London's high-security Belmarsh Prison, were asked questions that could rule them out of the case, including whether they or a relative had been caught up in a terrorist attack and whether they held strong political or religious views that would influence their verdict in the trial.

A jury of 12 will be selected Friday, and the prosecution is due to open its case Monday.

Eleven people -- including Osman's wife, Yeshiemebet Girma, and her sister Mulumebet Girma -- have been charged with assisting the accused or failing to disclose information. Their trials are due to take place later this year.