Guilty: the ringleaders who plotted a terror spectacular to rival 9/11

Police hails success of the largest counter-terrorism operation since airline plot of 2006

Irfan Khalid (left), Irfan Naseer and Ashik Ali, all from Birmingham, who were found guilty at Woolwich Crown Court of being "central figures" in a terrorist bomb plot. Bottom left: a syringe found in the safe house in White Street, Birmingham. Bottom rig (West Midlands Police/PA Wire)

The ringleaders of a Birmingham-based extremist cell whose deadly ambitions were matched only by their incompetence are facing life terms after the unravelling of their plot for a terrorist spectacular to rival the September 11 attacks.

The gang planned to send up to eight suicide bombers to carry out attacks against crowds of people with rucksacks stuffed full of explosives with the intention of mass murder on a scale bigger than the 2005 attacks on the London transport network.

Their detailed plotting was captured on bugging devices as they drove around bragging about the damage they would inflict and during bomb-making experiments at a safe house in the heart of the second city's Muslim community.

The ringleaders - Irfan Naseer, 31, and Irfan Khalid, 27, - were part of new wave of British extremists identified by the security services who travelled abroad for training at al-Qa'ida camps in Pakistan specifically to carry out attacks in their homeland. Security sources said it was remarkable how swiftly they had identified key figures in the al-Qa'ida operation.

The trial judge, Mr Justice Henriques, told the trio that they will all face life in prison when they are sentenced in April or May with Naseer “a highly-skilled bomb maker” facing a very long minimum term.

He said it was clear that the group was planning a terrorist outrage in Birmingham. "You were seeking to recruit a team of somewhere between six and eight suicide bombers to carry out a spectacular bombing campaign, one which would create an anniversary along the lines of 7/7 or 9/11.”

The two Irfans were also in contact with Lashkar-e-Taiba, the extremist group behind the coordinated attacks on hotels, the railway station and other targets in the Indian business capital of Mumbai in 2008, according to security sources. It can be revealed today that members of the gang had links with other convicted British extremists including a man accused of being the "terrorist's favourite bookseller". But in one recorded comment, Khalid said: "It's not for any group it's for Allah."

In the first known case of a potential suicide bomber making a part-confession to British anti-terror police, the third key player in the plot, Ashik Ali, 27, told police that they had considered attacks against British soldiers. However the gang never identified a target. Counter-terrorism police arrested the three leaders less than a year before the start of the Olympics - but the men indicated on secretly recorded tapes that they would be dead before the Games started.

They had also spoken of mixing poison with hand cream and smearing it on car doors overnight to trigger a mass killing when they headed to work in the morning.

The attack was to be paid for by funds raised in the name of Muslim Aid with the chief fundraiser for the group a collector for the charity dating back to 2009. Police say the charity was an innocent dupe in the plot and the regulator, the Charity Commission, said there was no investigation into the group. Police, however, are continuing a financial investigation to discover whether the men funded other terrorist plots.

In a statement, Muslim Aid said it welcomed the conviction of the charity collectors. "We would like to reiterate that Muslim Aid is a victim of this fraudulent activity."

Naseer, a 23-stone mastermind known as Chubbs, and his sidekick Irfan 'Sylvester' Khalid twice travelled to Pakistan for terror training where they hid from drone attacks, fired weapons and practised with explosives, according to their recorded accounts. Police believe they also made suicide videos which have never been recovered.

On their return, they worked with the cell's treasurer Rahin Ahmed and the owner of the safehouse, Ashik Ali, to plot their attack. They were among a group of 11 people accused of involvement in the plot.

But they were already under surveillance as soon as they returned from Pakistan and police charted a series of setbacks by a group that had likened itself to the "Four Lions" - the film about an incompetent bunch of would-be suicide bombers.

* Treasurer Rahin Ahmed lost £9,000 trading online when he left his screen to make a cup of tea. It was the "most expensive cup of tea we have come across in anti-terrorism work", according to a security source.

* Plans to send four young men to train in Pakistan were scuppered when one of the travellers phoned his family and gave away where they were. A family member - a Pakistani policeman - tracked them down and sent them home.

* Experiments using "explosive" ingredients of injury cold packs failed - when the plotters, who included a trained chemist, failed to realise that the materials used had been changed.

Police hailed the success of the largest counter-terrorism operation since the airline plot of 2006 and said the men had the motivation, ambition and ability to commit the acts. The group were said to have been inspired by the US-born cleric Anwar al-Awlaki, who was killed in a drone strike in Yemen several weeks after they were arrested.

Naseer, a pharmacy graduate, sketched out a formula for an explosive that was only partially destroyed and recovered by officers.

West Midlands Police Assistant Chief Constable Marcus Beale said: "No one should underestimate the seriousness of what these men were plotting.

"We had got them under close surveillance, which meant we were able to intervene at an early stage before there was any serious risk to public safety. But had they been able to continue with their plans, the consequences could have been worse than the London bombings of 2005. “

THE YOUNG MEN SENT TO PAKISTAN FOR TERROR TRAINING

Irfan Naseer and Rahin Ahmed were instrumental in sending four young local men - Ishaaq Hussain, Naweed Ali, Khobaib Hussain and Shahid Khan – to Pakistan for terror training. The four bought flight tickets, and flew to Pakistan in pairs on different days in late August 2011. However, they only stayed a few days because the family of one of them, initially unaware of their plans, discovered where they had gone and arranged for their return. Three of them returned within three days, while one, Shahid Khan, remained in Pakistan, apparently staying with family, until his return to the UK in early October. Following the return of three of the four travellers, Irfan Khalid and Ashik Ali were present and involved with Irfan Naseer at a debriefing of Ishaaq Hussain, one of the travellers. The tenor of their discussions, which were secretly recorded, demonstrates that they too were well aware the four had been sent to Pakistan for training, and of the dangers to them of Naseer being exposed for having sent them.

Paul Peachey