The FBI is closely watching dozens of Iraqis and others living in the United States in a wide-ranging security plan meant to deter any reprisals for a U.S. invasion. The nation's terror risk alert level was raised from yellow to orange following an address by President Bush telling Iraqi President Saddam Hussein to leave the country or face military action.

Some of those under FBI watch have been identified through ongoing interviews of up to 50,000 Iraqis. Others are suspected of having links to Al Qaeda and other terror groups, possibly including the Hamas and Hezbollah organizations blamed for suicide bombings in Israel.

The interviews with Iraqis are "designed to obtain any information that could be of use to the United States during a possible conflict," Jeffrey Lampinski, special agent in charge of the FBI's Philadelphia field office, said Monday.

The surveillance is part of a broader plan by the federal government, along with state and local law enforcement officials, to raise the nation's level of counterterrorism vigilance as the prospects for war increased. Many thousands of law enforcers are involved.

Some Muslims and Arabs fear war might result in harassment or deportation. One group, the Council on American-Islamic Relations, e-mailed a "community safety kit" to mosques, community centers and others Monday that describes steps people can take to deal with backlash from a U.S.-Iraqi war and urging cooperation with police.

"All of us are going to be suspects," said Sarah Eltantawi, spokeswoman for the Muslim Public Affairs Council. "There is just this profound sense of disappointment about what America is becoming."

FBI spokesman Mike Kortan called the plan a prudent approach to give the country the best protection possible.

Law enforcement officials believe war with Iraq could become a catalyst for attacks on the United States or its interests abroad, possibly involving single individuals with explosives strapped to their bodies.

U.S. counterterrorism officials say operatives working for Iraq's Mukhabarat, President Saddam Hussein's intelligence service, could attempt bombings or other traditional terrorist-style attacks. Many are thought to work out of Iraqi embassies around the world under diplomatic cover. The State Department recently sought the expulsion of some 300 suspected operatives from more than 60 countries, but many have not been removed.

Al Qaeda also may use the fighting as an opportunity to strike, although the most specific information points to possible attacks on U.S. forces in the Middle East. Officials say they have no credible information Al Qaeda is close to launching a strike inside the United States. A recent statement from Usama bin Laden, the Saudi-born leader of Al Qaeda, declared some solidarity with Iraqis, although he referred to Saddam's government as infidels.

The security plan, a year in the making, would divert several thousand FBI agents away from regular duties to focus solely on counterterror and security. The 56 FBI field offices will set up 24-hour command centers working with the 66 joint terrorism task forces that include other federal, state and local law enforcement agents.

Their job will be to react quickly to any intelligence data, including that collected by the United States in Iraq, or other information indicating that terror is being planned or is imminent. They also will focus on potential targets, keeping closer watch on critical infrastructure such as dams, bridges and power plants, and react to any hate crimes directed against Muslims or Arab-Americans.

Immigration officials are prepared to detain anyone identified by the FBI in violation of immigration laws.