Three British Islamists are on trial in Britain, facing accusations of plotting terrorist attacks that could have been deadlier than the 2005 London transit bombings.

Prosecutor Brian Altman told a high-security London court Monday the three defendants planned to detonate up to eight rucksack bombs in a suicide attack or set off timer bombs in crowded areas. He said the plot was “on a scale potentially greater” than the July 7, 2005 bombings that killed 52 people on London's underground train and bus networks.

Defendants Irfan Naseer, Irfan Khalid and Ashik Ali have pleaded not guilty to terrorism charges. Authorities arrested the men in the city of Birmingham in September 2011.

Altman said the defendants were inspired to commit terrorism by the anti-Western sermons of U.S.-born radical cleric Anwar al-Awlaki, an al-Qaida loyalist killed by a U.S. drone strike in Yemen last year.

The prosecutor said the plot began with Naseer and Khalid traveling to Pakistan for training, learning how to make poison and bombs and producing martyrdom videos. After returning to Britain, he said they worked with Ali to recruit others to the plot and to raise money fraudulently by posing as fundraisers for Muslim charities.