British authorities have charged eight men with conspiracy to murder, in an anti-terrorist round-up spurred by information gathered from a computer expert arrested in Pakistan last month.

The men, all of Asian-origin aged between 19 and 32, were apprehended two weeks ago in a series of coordinated raids throughout Britain.

Under British law the men had to be either charged or released.

They have been held and questioned during the past 14 days at the high-security Paddington Green police station in London.

The eight were initially detained along with five others who have since either been released or held on lesser criminal charges.

Besides murder conspiracy charges, the eight men are accused of conspiracy to commit a public nuisance by using radioactive material, toxic gas, chemicals or explosives.

One of the defendants, 32-year-old Dhiren Barot from north London, also is accused of possessing reconnaissance plans of the New York Stock Exchange, the Citicorp headquarters, and the Prudential building in New Jersey.

The men will make their first court appearance on Wednesday.

It could lead to the most high-profile terrorism trial in Britain since September 11, 2001.

British authorities have said very little about those in detention, but U.S. officials have commented that among those arrested in Britain are some key figures in the al-Qaida network.

The arrests were made on August 3, one day after the disclosure by U.S. newspapers of the name of a computer expert being held in Pakistan. It is believed that information contained on Mohammad Naeem Noor Khan's lap-top led to the recent heightened Orange-level security alert in New York, New Jersey and Washington.

At the time, Pakistani intelligence sources said releasing Mr. Khan's name into the public domain had exposed his part in what was described as a "sting" operation.

British authorities say they were unable to apprehend all of those they would have liked to have questioned and a number remain at large.

Since September 11, Britain has arrested more than 600 terrorism suspects, but has charged fewer than 100. Fifteen have been convicted of terrorist offenses.