Updated

The recent arrests of nine British Muslims and the capture of half a ton of bomb-making fertilizer are raising fears of a homegrown terrorist threat.

Days after the arrests, an angry crowd burned a British flag outside a central London mosque.

The fear of Al Qaeda (search) dispatching foot soldiers to Britain for suicide missions has morphed into a real concern about an enemy within, according to interviews with Britons and security experts. Homegrown terrorists are a growing worry for the British government and its citizens.

"The aim of the militants was always to spread their ideology and have them act independently, autonomously, and what we have seen in the U.K. is people acting in the style of Al Qaeda in accordance with Al Qaeda's ideas but not part of Al Qaeda," said Jason Burke, a journalist for the Guardian in London.

Some British Muslims are ready and willing to attack targets in their own country, a country they are increasingly turning against.

"I think Tony Blair is playing with fire and if you play with fire, it's only a matter of time before he gets burnt," said Khalid Kelly (search), an Irish convert to Islam who lives in Britain.

And while such extremists are ratcheting up the angry rhetoric and insisting that Muslims are at war with the ways of the West, moderate Muslim voices are saying such talk is totally un-Islamic.

"We need to isolate these people. More and more young people need to speak out against these elements, that they are nothing to do with Islam," said Iqbal Sacranie of the Muslim Council of Britain (search).

Just last week, the Muslim Council appealed to 1,000 mosques in London to begin preaching that terrorism is wrong and take action against extremists.

Click here to watch a report by Fox News Channel's Amy Kellogg.