Police on Tuesday arrested eight Britons in an early morning raids in and around London and seized half a ton of what was described as bomb-making material, the London Metropolitan Police said.  

The eight men, aged 17 to 32, were held under anti-terrorist laws after the raids in Uxbridge, Crawley, Ilford, Slough, and Horley.

The bomb-making material -- ammonium nitrate -- was seized from a self-storage facility in west London, said Peter Clarke, head of the Metropolitan Police anti-terrorist branch, adding that it was used in the October 2002 blast in Bali that killed 192 people.

The substance was also used in a suicide bomb attack in Istanbul in November as well as in attacks in London and Northern Ireland by the Irish Republican Army.

But Clarke said that the operation was unconnected with the Madrid train bombs earlier this month or with Irish republican terrorism.

He added that as many as 700 police officers carried out a total of 24 searches which targeted residences and business properties.

(Xinhua News Agency March 31, 2004)