LONDON (CP) - The arrests of nine terrorist suspects in Britain and one in Canada last week began with a message intercepted by the National Security Agency in the United States that appeared to give instructions for an attack in the United Kingdom by al-Qaida commanders in Pakistan, The Sunday Times reports.

The newspaper says the message was received by computers at the NSA's electronic eavesdropping centre in Maryland, which monitors millions of telephone calls and e-mails a day.

Police in Britain were alerted of the threat after the NSA analysed the automatic translation of the communication that The Sunday Times said was "thought to be between Britain and Pakistan."

[. . . .] The newspaper said the original tip, picked up by NSA satellites, was given high priority because it appeared to be instructions for an attack passing between Al-Qaida commanders in Pakistan and associates in Britain.

The sender was apparently in the circle around Abu Musab al-Zarqawi, believed to be the mastermind of attacks in Baghdad and Karbala last month in Iraq that killed 280 people during a Muslim religious festival.

The link to Pakistan is also seen as significant because it disproves a view that al-Qaida's command structure had been broken up and scattered by the fall of the Taliban in Afghanistan and arrests made around the world in the last 2 1/2 years of the war on terror, The Sunday Times said.

"We all thought there were cells operating in isolation and had been told that the al-Qaida network had been destroyed from the top when suddenly we find a chain of command leading back to Pakistan," a senior Scotland Yard source is quoted as saying.