LONDON — Three men accused of plotting what prosecutors said would have been the most devastating terrorist attacks in Britain since the London transit system bombings of July 2005 were convicted Thursday after a 12-week trial. The judge hearing the case told the men to expect sentences of life imprisonment.
Prosecutors said the three men — Irfan Naseer, 31, Irfan Khalid, 27, and Ashik Ali, 27, all British citizens from the industrial city of Birmingham in the English Midlands — planned to detonate up to eight homemade bombs in rucksacks in crowded places, the method used by the four suicide bombers who killed 52 other people on London subway trains and buses in 2005.
That attack prompted MI5, the domestic security service, and police forces across the country to rapidly expand their counterterrorism efforts. Officials at MI5 and at Scotland Yard have said that the authorities track dozens of active terrorist cells, and they cite a series of successful prosecutions and the absence of any attack that led to mass casualties in Britain since the transit bombings as evidence of their success.
The court in Birmingham was told that the authorities had the three defendants under close surveillance from an early stage, along with nine co-conspirators, six of whom have pleaded guilty to terrorism charges. The police officer who led the surveillance, Detective Inspector Adam Gough, described the three men, all Muslims, as “committed, passionate extremists,” and added, “They had a real stated intention to kill and maim as many people as they possibly can.”
The men were still discussing potential targets and weapons when they were arrested in September 2011 as they drove across Birmingham, prosecutors said. From bugged conversations and police questioning, the court heard, the men were known to have discussed using rucksack bombs, rifle attacks on crowded streets and targeted strikes against British soldiers; more arcane methods were also mentioned, including putting poison on the car-door handles of intended victims and fitting long blades to the hoods and wheels of cars to be driven onto crowded sidewalks to scythe people down.
Mr. Naseer, said to be the ringleader, was described at the trial as a “fantasist” who had been teased and nicknamed Chubby at school for being overweight and who resolved as he grew into adulthood, gaining a pharmacy degree, to make a name for himself as a violent jihadist. He and his associates spoke frequently of their hatred for Britain, particularly after British troops occupied Afghanistan and Iraq, the prosecution said.
Two of the men, Mr. Naseer and Mr. Khalid, were tracked by the security services leaving Britain and entering terrorist training camps linked to Al Qaeda on the Pakistan-Afghanistan border. Later, the prosecution said, the two arranged for four other young Birmingham men to travel to Pakistan for terrorist training. Those four were among the six who pleaded guilty at an earlier trial.
The prosecution said that the three main Birmingham plotters were overheard criticizing the 2005 transit attackers for failing to include loose nails in their bombs to make them more lethal. The court heard that Mr. Naseer and his fellow plotters were heavily influenced by the extremist propaganda of Anwar al-Awlaki, the American-born cleric who was killed by an American drone strike in Yemen in September 2011. They learned of Mr. Awlaki’s teachings from an English-language magazine, Inspire, that was founded by Mr. Awlaki and distributed over the Internet, the prosecution said; it claimed that it was from the magazine that they took the idea of attaching blades to the wheels of cars and creating what the magazine called “the ultimate mowing machine.”
