Birmingham’s bustling inner city suburbs of Sparkbrook and Sparkhill found itself on the front line of Britain’s war on terror even before the hijacked airliners smashed into the Twin Towers 12 years ago.

Police raided the “bomb factory” home of former waiter Moinul Abedin in January 2001 smashing what has since been described as the UK’s first home grown al-Qa’ida plot.

Since then the security forces have made repeated visits to the city’s celebrated Balti Triangle and its Pakistani, Kashmiri and Bangladeshi neighbourhoods to mounting alarm from community leaders. Each raid, with its hurtling convoys of police vehicles, screaming sirens and taped-off streets, brings a new sense of shock and dismay.

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According to research by the Henry Jackson Society, more convicted British Islamic terrorists have come from Birmingham than anywhere else outside London. Others including five Britons convicted of plotting bomb attacks in Yemen in 1999 and the so-called Tipton Taliban also have links to the city.

In 2010 when the local community reacted angrily to the revelation that police had installed vehicle recognition surveillance cameras to track suspected terrorist activity in the Muslim areas off the busy Stratford Road corridor, the police justified their actions by pointing out that there had been 11 terrorist-related convictions in Sparkbrook and nearby Washwood Heath in the previous three years.

These included Parviz Khan from Alum Rock who was jailed for 14 years for plotting to kidnap and behead a British soldier.

The later conviction for publishing extremist texts of Ahmed Faraz, who operated the local Maktabah bookshop and whose customers included the July 7 bomb plot leader Mohammed Sidique Khan, further stoked official interest in the area – even after many of his charges were quashed by the Court of Appeal.

Terrorism experts now point that despite more than 15 convictions since 2001 nearly all have now returned to their communities after serving half of their relatively short sentences. But local people believe the ideas that underpin violent extremism do not come from within but outside.

Muhammad Suleman, 60, a former welder and community elder, believes young men, isolated from their families, frustrated by a lack of prospects and angered at Western military intervention in the Muslim world come under the influence of militant propaganda which contradicts the teachings of Islam. “A lot of young people don’t go to mosque. They learn on the internet. It is information you can’t hide and they make their own mind up,” he says

“Young people have no experience of life. They are emotional and get upset and may take the law into their own hands,” he adds. “Those who are criminals should be punished but don’t criminalise the whole community. You give the lead to all the racists and people who are anti-muslim,” he warns

At the UK Islamic Mission mosque on Stratford Road – one of 16 places of worship within the surrounding streets- more than 400 people cram into Friday prayers each week including the family of Ahmed Faraz. The Imam, Muhammad Sajjad, originally from North West Pakistan, said the mosques do their best to combat extremism. “Terrorists have no religion - a terrorist is a terrorist,” he says.

However, he is also aware his message competes against the background of international events.

“I know the people who are the victims of the drone attacks. They are very, very poor. They need education. If you give them money for education they become your friend. If you kill them they will become your enemy,” he says.