The assault appeared imminent. U.S. forces cited Allawi's emergency decree in announcing that they had sealed off the city late Sunday, declaring in a statement that troops were "finishing final preparations for an assault on Fallujah."
Senior Marine commanders gathered troops for hollered pep talks, invoking the 1968 assault on the Vietnamese city of Hue, a battle that looms large in the lore of the Corps.
"The window is closing, absolutely," Allawi said, adding that Fallujah residents "have been taken hostage by a bunch of terrorists and bandits and insurgents who were part of the old regime. They had been involved in atrocities when Saddam [Hussein] was around. Our government is determined to safeguard the Iraqi people."
Allawi's warning was immediately answered by a Sunni group that has been a leading voice for the resistance.
"This will increase the violence," said Mohammed Bashar Faidhi, spokesman for the Association of Muslim Scholars, which represents 3,000 Sunni Muslim clergy in Iraq. "The government is like a man walking in the dark who wants to avoid a small hole and falls into a big hole."
"At this point, the government can't even protect itself," Faidhi said. "How can it impose a state of emergency? Allawi, when he travels, half of the American Army accompanies him!"
Faidhi said the clerics' association supported a proposal aimed at reducing support for armed struggle by addressing Sunni concerns about U.S. influence on the election process and restricting the movements of U.S. forces. But Faidhi said the group's skepticism was being realized as preparations for the assault on Fallujah advanced.
"After breaking into Samarra, new people joined the resistance in order to get revenge," he said. And if Fallujah is attacked, "I don't exaggerate when I say the resistance will double."
In Haditha, about 30 insurgents mounted a three-hour coordinated assault on the city's police headquarters starting at 9 p.m. Saturday.
"First of all, we were attacked by mortars," Lt. Muneef Abdullah said. "Then the armed men came and started shooting and throwing hand grenades. When we tried to defend ourselves, they started launching" rocket-propelled grenades.
"We called the Americans to come and help us," he said, "but unfortunately they took three hours, as if they were coming to a wedding."
Other accounts of the attacks on the police stations in Haditha and Haqlaniya, in western Anbar province, which includes Fallujah, said that some of the Iraqi police officers were killed execution-style. The Reuters news agency said the attackers took the captured policemen to an oil-pumping station and shot them to death.
Last month, insurgents massacred 49 unarmed Iraqi army recruits after capturing them on a road northeast of Baghdad. A group led by Abu Musab Zarqawi, a Jordanian linked to al Qaeda, asserted responsibility for those killings.
Special correspondent Saad Sarhan in Najaf contributed to this report.