Two Muslim men were sentenced to prison on Tuesday after being convicted of possessing documents useful to terrorists including information on how to make weapons and explosives.

Judge Timothy Pontius set a 12-year sentence for Aabid Khan, 23, who allegedly was a key figure in radicalizing young people, including an 18-year-old man — Hammaad Munshi — who was involved in the same case and faces sentencing next month.

Khan's co-defendant, Sultan Muhammad, 23, was sentenced to 10 years in prison.

Sentencing was interrupted by Khan's father, Sabir Khan, who accused the judge of being anti-Muslim.

Khan was convicted by a jury on Monday of three counts of possessing articles for a purpose connected with terrorism.

Muhammad was found guilty of three similar charges and a charge of making a record of information likely to be useful in terrorism.

The prosecution said the two men had computer files promoting violent jihad, documents with practical information on making and using weapons and explosives, and one that urged assassinations.

Pontius said the defendants were not guilty of attempting or planning to attempt an act of terrorism, "but rather of possessing articles intending they should be used in some way at some future time of preparing and instigating acts of terrorism, the precise details of which, such as time and place, had yet to be finalized."

Pontius added that the material seized by police "is amongst the largest and most extensive ever discovered and thus makes this case one of the most serious of its type to come before the courts."

Prosecutors said Khan enlisted Munshi, then a 15-year-old boy, as a supporter of violent jihad. Prosecutors said Munshi downloaded detailed instructions about making napalm, other high explosives, detonators, and grenades, and "how to kill."

Munshi is the youngest person to be convicted of a terrorist offense in Britain, the Crown Prosecution Service said.