Walid Saadaoui, 38, and Amar Hussein, 52, were convicted of plotting a terrorist attack in Britain, inspired by the ISIS organization.
The two men had planned to carry out a mass killing spree and use automatic weapons to kill as many Jews as possible, according to their testimony.
The British police and prosecution stated that if their plans had succeeded, they could have resulted in "one of the deadliest terror attacks in the history of the UK, if not the deadliest."
According to Deputy Police Commissioner Robert Potts, the two had planned the attack over an extended period of time and were very close to carrying it out.