WASHINGTON, Oct 26: An anti-terrorism bill that gives wide-ranging powers of detention and surveillance to the government was signed into law on Friday by President George Bush.

The measure will particularly affect illegal immigrants or those suspected of being illegal immigrants by permitting federal authorities to detain such people for up to seven days instead of the current 48 hours, and in some cases this could be repeatedly extended by six-month periods.

The act has raised widespread concern among advocates of civil liberties, and in normal circumstances would have been seen as an oppressive piece of legislation by US standards. But the situation has drastically changed since the Sept 11 attacks and the current outbreak of anthrax exposure cases, and the bill was passed by overwhelming majorities in both the House of Representatives and the Senate.

It bestows on the executive wiretap powers for four years, and investigators will now be able to read e-mail, collect data on computers, and track suspects via the Internet.

The legislation incorporates provisions that aim to cut off financing channels for suspected terrorist networks. The provisions include new rules barring US banks from most dealings with overseas “shell” banks that have no physical presence anywhere. They impose new requirements on so-called “correspondent accounts”, which allow foreign banks to use US banks’ services, thus giving them direct access to the American financial system.

They also require financial institutions that establish or administer correspondent accounts to establish appropriate “due diligence” policies for detecting and reporting instances of money laundering through those accounts.

The law gives the US Treasury additional powers to target foreign countries and banks believed to present a money-laundering threat and makes it illegal to smuggle more than $10,000 in cash in or out of the United States.