LONDON (AFP) - Police arrested four men in London under Britain`s anti-terrorist law, as a Sunday newspaper claimed it had infiltrated a gang trying to buy radioactive material for a "dirty bomb".
The Metropolitan Police said the four men -- arrested under the Terrorism Act 2001 -- had been taken into custody at a central London police station "for further questioning".
"Several addresses have been searched," a police spokesman said. "Some searches continue."
All four men -- whose names were not released -- were detained under section 41 of the Terrorism Act, which refers to "the (suspected) commission, preparation or instigation of acts of terrorism".
The News of the World said it cooperated with police after it infiltrated a gang that claimed to be looking for radioactive material on behalf of a Saudi "described as sympathetic to `the Muslim cause`."
The Saudi, whose name was not disclosed, was reportedly willing to pay 300,000 pounds (441,500 euros, 541,000 dollars) in cash for a kilogram of "highly powerful radioactive material" from Russia known as Red Mercury.
The News of the World said the material was developed by Soviet scientists during the Cold War "for making briefcase nuclear bombs" that could kill all people within a few city blocks.
"It is very, very radioactive," a member of the gang was quoted as telling Mazher Mahmood, the News of the World`s star investigative reporter, who posed as a Muslim extremist.
"The guy (from Saudi Arabia) said it is used for making bombs. It`ll either be for use here in the United Kingdom or in the United States," the gang member reportedly said.
The gang consisted of a banker originally from Goa, India, his "sidekick" from Mozambique, and a Somalian formerly resident in Saudi Arabia, while the Saudi was said to have successfully applied for a visa to enter Britain.
Police said three of the suspects were arrested at a hotel in the Brent Cross district of north London, while the fourth man was taken into custody at his north London home.
That dovetailed with the News of the World`s description of elite anti-terrorist officers raiding a Holiday Inn at Brent Cross. The newspaper did not indicate how the fourth suspect was arrested.
Later Saturday evening, a Metropolitan Police spokesman confirmed that investigators were "acting on information received from the News of the World".