Quotes of the Day

When Defense Secretary Donald Rumsfeld warned two of Iraq's neighbors, Syria and Iran, against helping Saddam Hussein, he wasn't just worried about military gear crossing the borders. U.S. intelligence has been picking up indications that Muslim extremists from Islamic Jihad, Hizballah and Iranian Shi'ite groups have started entering Iraq from both countries, as well as from Jordan.

A senior U.S. official told Time that his main security concern in Iraq, once Saddam is ousted, is "not the remnants of Saddam's government. It's the presence of other radicals who may owe their allegiance to neighboring regimes that have their own agenda."

Intelligence reports aren't conclusive about the number of terrorists who have entered, but small groups of Islamic Jihad and Hizballah agents have already infiltrated the country, and "we've got people paying attention to both approaches, from Syria and Jordan," says a U.S. counterterrorism official. Modest numbers of Iranian Shi'ites have also managed to enter Basra in southeastern Iraq to support Iraqi Shi'ites there; British and U.S. troops have warned them to stay out of the way of coalition forces.

The fear is that these radicals could incite more suicide bombings aimed at U.S. troops. Yet it's far from certain that these groups could combine to form a significant threat. Hizballah and the Islamic Jihad share few values with Saddam's Baathist nationalists. And Iraqi Shi'ites and Iranian Shi'ites are not ideological soul mates; fears after Gulf War I that the two would join up to carve out a separate state aligned with Iran proved to be unfounded.

Some even speculate that the infiltration could aid U.S. efforts to track down terrorists. "There's one school of thought that says, 'Bring them on, let them all come to Iraq,'" says the U.S. counterterrorism official. "It would be easier for us to kill them in Iraq than anyplace else."

• Timothy J. Burger and Douglas Waller