Five men were arrested today over their alleged role in protests against cartoons satirising the Prophet Mohammed.
Four of them were held on suspicion of incitement to murder and all five are suspected of "using threatening words or written material to stir up racial hatred".
It follows protests outside the Danish Embassy in London on February 3 and 4 when placards threatening a repeat of the September 11 or July 7 terror attacks were waved.
Four of the men arrested today were held in London and one in the West Midlands.
The four men in London were arrested at their homes in Tower Hamlets, Redbridge, Southall and Waltham Forest.
They were taken to a central London police station for questioning.
A fifth man is being questioned in the West Midlands.
They are alleged to have taken part in the February 3 demonstration.
A Scotland Yard team has been studying video, photographs and sound recordings of the February 3 demonstration.
The material includes 60 hours of video footage from CCTV cameras. There were also 500 complaints about the demonstration.
Police later handed a file to the Crown Prosecution Service and were advised there were "sufficient grounds" for prosecutions.
To date 22 people have been considered for prosecution and police are trying to identify all of them.
Up to now, the only arrest had been that of Omar Khayam, a 22-year-old protester who dressed as a suicide bomber during the second day of demonstrations.
He was not charged with any offences but was returned to jail for breaching the terms of his parole for possessing crack cocaine with intent to supply.
During the spontaneous February 3 march from the Central London Mosque to the Danish Embassy protesters praised the "magnificent" 9/11 hijackers and waved placards with messages such as "Massacre those who insult Islam", "Europe you will pay" and "Europe you'll come crawling when Mujahideen come roaring".
Shadow home secretary David Davis has previously written to Home Secretary Charles Clarke attacking the "unconscionable" delay in making arrests.Reuse content