LONDON — The British police on Tuesday charged eight men with conspiracy to murder and violations of the Terrorism Act after finding that two of them possessed surveillance information on the financial centers in Washington, New York and New Jersey that were the focus of the terror alert earlier this month in the United States.

The eight men were arrested on Aug. 3 and have been held at a high-security police facility in West London. Under the two-week deadline set by the Terrorism Act, the police had until Tuesday to bring charges against the men or release them.

A statement issued by Scotland Yard made no assertion that the police had interrupted an active or specific plot against any of the financial center targets in the United States, or that the suspects had access to explosives, toxic gases or radioactive materials. A police official said no such material had been seized.

"The British were very concerned," a senior European counterterrorism official said. "They have apprehended what they feel is a live cell."

Among the eight men was an alleged ranking operative of al-Qaida whom American law enforcement officials had earlier identified by an alias, Issa al-Hindi, which means Issa the Indian. British officials Tuesday said that one of the men they were charging, Dhiren Barot, 32, was also known as Issa al-Hindi and was believed to be a senior al-Qaida representative in Britain.

Barot is also believed to have conducted surveillance activities in the United States in 2000 and early 2001 under the alias Issa al-Britani, or Issa the Briton, according to the report of the Sept. 11 commission.

The terror alert in the United States was elevated on Aug. 1 after Pakistani authorities made a series of arrests of Qaida militants. Among them was a 25-year-old computer technician, Mohammed Naeem Noor Khan, in whose possession the police found a large and detailed computerized archive of surveillance information on the International Monetary Fund and World Bank in Washington, the Citigroup tower in Manhattan, the New York Stock Exchange and the Prudential Building in New Jersey.

The eight men were identified as Barot; Omar Abdul Rehman, 20; Zia Ul Haq, 25; Abdul Aziz Jalil, 31; Nadeem Tarmohammed, 26; Mohammed Naveed Bhatti, 24; Qaisar Shaffi, 25; and Junade Feroze, 28.

A ninth man, Matthew Philip Monks, 32, was charged with firearms possession.