The mosque, in a dingy office block overlooking High Wycombe's railway station, was visited regularly by four of the six men arrested by antiterrorism officers in this affluent Buckinghamshire town in the early hours of Wednesday.

Such was the fear of a backlash yesterday on Islam's day of prayer that one man deliberately left his sons, aged eight and 10, at home. A police statement handed out to worshippers explained that the uniformed constables outside were not there in search of evidence but to dissuade what one officer described as "white lager louts" intent on fanning racist sentiment.

As the officer put it: "You know the sort of thing . . . a window wound down and an idiot shouting 'Oi, Bin Laden'. These people could do without that right now."

Within a square mile of the prayer room, cooled by a dozen ceiling fans, lie the five homes at the centre of the investigation into the alleged plot to blow up airliners. Little surprise, therefore, that the mood among High Wycombe's Muslims . . . and the other places in Birmingham and east London where arrests took place . . . was one of introspection, anxiety and, for some, raw anger. This, after all, is a town so well integrated into Home Counties life that it has a Muslim Chamber of Commerce.

Khan, 32, wearing a white shalwar kameez over baggy jeans and trendy trainers, once lived next door to one of the six suspects arrested in High Wycombe, Waseem Kayani, a 29-year-old taxi driver .

Like many of the town's 11,000 Muslims, Khan could barely conceal his astonishment and concern that the town will become synonymous with home-grown terrorism.

The IT worker said: "It's six guys out of more than 10,000.

But it's really hard not to take it personally. I knew this guy, Waseem. I don't know if he did what he is accused of, and if he did then they should throw away the key. But my point is he was a taxi driver, an ordinary bloke who used to drink too much. It's like anybody can be a terrorist, like there's a banner over High Wycombe now that says Muslims here are terrorists."

Community leaders in Totteridge, where about 2,000 Muslim families live, underlined pre-existing programmes at Islamic youth clubs and schools to counter extremism. Ifath Nawas, a High Wycombe resident and chairwoman of the Association of Muslim Lawyers, said:

"There has been enormous effort put into maintaining the cohesion between the faith groups in this town. It has been a success story which we cannot allow to be destroyed."

But outside the Totteridge mosque, others saw a straightforward root for the plot . . . "diabolical and about as contrary to Islam as you can get" as one worshipper put it . . . alleged to have been nurtured secretly in their midst.

Allah Ditta, 19, said: "You know what's behind this, don't you? It's British foreign policy.

I know people don't like to hear it, but it's true. When you put young guys in front of images that show the result of what goes on in Palestine, Iraq, Afghanistan, Lebanon, some of them will flip. It's not the right conclusion but it's idiotic to pretend that it won't be reached by some."

In Walthamstow, east London, where 10 of the suspects live, there was concern that the headlines and politicking of the previous 24 hours might supersede the legal process.

Mohamed Shoaib, imam of the Queen's Road mosque where some of the suspects worshipped, said: "Everybody is concerned about the events.

Be mindful of the fact that people are innocent until proven guilty. Our thoughts and prayers are with the families at this time."

Caslim U Khan, 46, has worshipped at the Queen's Road mosque for 20 years. "This is very sad. I'm afraid for the community. This is a very peaceful mosque . . . people pray, they live in this country and respect this country. I do hope they are innocent. I do hope, " he said.

Concern at the prospect of reprisals was raised after police confirmed they were investigating if an arson attack at a mosque in Chester was linked to the terror plot.

Youths attacked the building in Blacon shortly before midnight on Thursday while people were still inside. The small blaze was quickly extinguished.

Human rights campaigners said much of the unease and scepticism among Muslims has been fuelled by botched anti-terrorist operations such as the shooting of an unarmed man during the raid on a home in Forest Gate, east London, in June.

Fahad Ansari, from the Islamic Human Rights Commission, said: "For four years we've been seeing more and more innocent people being harassed and demonised.

We've seen very few terrorists captured but a lot of innocent people destroyed."

But in Totteridge, frustration was expressed at those who, innocent or not, were being blamed for besmirching their name.

Iqbal Latif, 47, an accountant, turned down the music blasting from the speakers of his sports car long enough to say: "If these guys are guilty, I want to be the first to put them up against the wall.

It's disgusting. Whether they're Muslim or not is incidental."