By Steve SwannÂ
BBC News Home Affairs unit
Khan recorded his plotting in a diary
Aabid Khan’s conviction marks the latest chapter in a series of raids and arrests across three continents. Four trials have already led to convictions in three countries – and the investigations continue.
Armed police closed in on an apartment on a rutted road in a village on the edge of the Bosnian capital Sarajevo.
As they burst in, they subdued a group of men they had been observing. One of the group had an armed “suicide belt” of explosives.
These arrests in March 2005 were a major breakthrough in an investigation that would reveal how international jihadists were operating through the internet – from North America and Europe through to South Asia.
The searches in Bosnia uncovered a so-called “martyrdom” video explaining in English how the men were fighting on behalf of oppressed Muslims around the world.
Materials included the mobile phone belonging to the ringleader, who had travelled from Scandinavia hoping to carry out attacks on Nato targets.
The men shared material on suicide bomb-making
But just as importantly, detectives established the phone had been in contact with a number registered to an address in the UK.
When officers from the Metropolitan Police kicked in the door of a modest flat in west London, they had no idea they were about to arrest one of the then most significant figures among a growing network of cyber-terrorists.
The occupant was a young Moroccan, Younes Tsouli, who had used the internet to build links to al-Qaeda leaders in Iraq and a wider network around the world.
Robert Mueller, the Director of the FBI has described Tsouli as an example of how “the web is terrorism’s new frontier, offering both persuasive information, but also practical instruction”.
Tsouli’s encrypted hard drive was a treasure trove of evidence which led detectives to other suspected extremists across the world.
These men had been using password-protected internet forums to exchange views on jihad – but they did not realise they had also left themselves exposed to infiltration by intelligence officers.
Within a couple of months of Tsouli’s arrest, West Yorkshire Police officers began observing the activities of Bradford man Aabid Khan. He had worked on one of Tsouli’s key websites, At Tibyan.
How Khan is linked to other terror cases around the world
Meanwhile, in North America, police and spies began watching another group they linked to this online network. Like Tsouli and Khan, many of them were very young.
The targets they are alleged to have discussed attacking – the global positioning system and the Canadian Parliament – often seemed fanciful.
Khan allegedly talked online to some of them about setting up a mini-Sharia state in a remote part of Scotland.
Nevertheless, his naivety was combined with a deadly seriousness and burgeoning connections to militant groups in Asia.
Gradually, once evidence had been gathered of various alleged plots, the authorities moved to arrest those they had placed under surveillance.
Younis Tsouli described himself online as Terrorist 007
Two men from the United States were among those picked up in March and April 2006.
They are alleged to have emailed Tsouli and Khan reconnaissance footage they filmed of targets in Washington DC. Khan is then believed to have met one of the men in Pakistan to arrange terrorism training.
Scottish police arrested a student, Mohammed Atif Siddique, as he was about to board a flight to Pakistan to join up with Khan. Analysis of internet chat between him and Khan suggested the latter was grooming and radicalising the former.
Then in June 2006 Toronto witnessed the dramatic arrests of 17 men. The group had been infiltrated by two police informants and was accused of planning attacks on Canadian targets. The alleged leader was a friend of Aabid Khan’s. The men deny terrorism charges in an ongoing case.
Days later Khan flew back to Britain from Pakistan. Despite knowing about the arrests in Toronto, he entered the country with a mass of incriminating material.
Officers from West Yorkshire Police had been tipped off by the security service that Khan was coming into the country.
When they searched his luggage they were astonished to find evidence that dramatically illustrated his involvement in Islamist extremism and his dedication to the cause of the global jihad.
As he was cautioned, he asked officers: “Will my Dad get to know?”
When detectives said they needed to swab his hands as he was suspected of handling explosives, he started to shake violently.
“I’ve been handling fireworks in Pakistan,” he said.