Britain's youngest terrorist is facing jail after a guide to making napalm was found in his home.

Hammaad Munshi was just 15 when he joined an "online extremist support network" that distributed guides on how to manufacture bombs to kill non-Muslims.

The teenager is the grandson of Sheikh Yakub Munshi, a respected scholar who is president of the Islamic Research Institute of Great Britain and runs a Sharia law court in Dewsbury, West Yorkshire.

London's Blackfriars Crown Court heard how Munshi attended a local comprehensive school by day then spent hours surfing jihadist sites and distributing material to others in what prosecutors branded a "worldwide conspiracy" to "wipe out" non-Muslims.

He was 15 when he was recruited by Aabid Khan, 23, the brains behind terrorist web network At-Tibiyan Publications.

Khan was stopped after flying back from Pakistan at Manchester Airport in June 2006 and was found to have the biggest collection of articles promoting terrorism ever seized by police.

It included the addresses of Royals like the Queen, the Duke of Edinburgh and the Prince of Wales along with detailed instructions on making napalm, other high explosives, detonators, and grenades, and "how to kill".

Khan and Munshi swapped documents about "black powder explosives" and Khan gave his schoolboy protégé advice on how to smuggle a sword through airport security.

Munshi was 16 and taking his GCSEs at Westborough High School when he was arrested as part of a massive police investigation.

Two bags of ball-bearings were found in one of his pocket, al-Qaeda propaganda videos were found on his computer, and notes on martyrdom were discovered under his bed.

Khan, of Otley Road, Undercliffe, Bradford, West Yorkshire, was found guilty of three counts of possessing articles for a purpose connected with terrorism and cleared of a similar count.

Post Office worker Sultan Muhammad, 23, Khan's cousin and "right-hand man", of nearby Hanover Square, Manningham, was found guilty of three similar charges and one of making a record of information likely to be useful in terrorism.

Munshi, now 18, from Greenwood Street, Saville Town, Dewsbury, was found guilty of a making offence but not guilty of a possession offence.

Judge Timothy Pontius will sentence Khan and Muhammad on Tuesday but Munshi will be sentenced on September 19. The judge ordered him to be detained until then.

A fourth defendant, Ahmed Sulieman, 30, from south London, was cleared of three possession allegations after explaining the files found belonged to somebody else.

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