The outbound traffic formed a line of apprehension.

Residents of Chamchamal piled their belongings onto tractors, wagons, taxis, pickup trucks and even one lumbering front-end loader, its bucket brimming with blankets and clothes, joining a stream of vehicles headed away from the line that divides the autonomous Kurdish region of northern Iraq from the dominion of President Saddam Hussein.

"We are afraid of the army that is residing on the hill above Chamchamal," said Arif Jafar, sitting cross-legged on the side of the road with a faulty carburetor in his lap, his face turned toward the valley he had just escaped. "We're afraid they will attack us with chemical weapons."

Here and elsewhere along the jagged line that demarcates the 17,000-square-mile Kurdish enclave, people were on the move today. President Bush's words at the Azores summit conference Sunday seemed to have convinced the Kurds that war is on the way -- and that staying too close to the Iraqi military, with its history of using chemical weapons, is from now on a dangerous way to live.

The Iraqi army was visible on the hills around this town, which sits at the border on the main road about 25 miles northeast of Kirkuk, the regional center that is under Iraqi government control. Pimples of dirt rose on the horizon, a mile or so off, looking like earth piled around mortar and rocket emplacements.

"There are reasons not to feel safe in Chamchamal," said Rizgar Ali, an official of the Patriotic Union of Kurdistan, the party that governs the section of northern Iraq northeast of Kirkuk.

Fearful departures also accelerated in another Kurdish city, Irbil, about 70 miles northwest of here and only 20 miles from the dividing line. Families began fleeing at dawn, and the pace picked up as night fell. Motorists lined up for gas as the price increased, and some merchants stripped their stores of merchandise for fear of looting should chaos break out.

"I am sending my wife and children away because we have experience. Things can go badly," said Amjad Abu Bakr, a grocery store operator in line at a gas station on the road northeast from Irbil toward the mountains. "We are worried that chemical weapons might reach Irbil. Every Kurd has this in his mind."

Kurdish officials said many of the new refugees, including those from areas under Iraqi control, will be housed with private families or in tent camps projected for construction north of Irbil. But the Kurds are still awaiting delivery of the tents from relief agencies and the United Nations, they said.

Kurdish officials in the western zone, administered by the Kurdistan Democratic Party, or KDP, warned that Iraqi artillery near the front lines could send shells onto Irbil as well as Dohuk farther north. They are counting on U.S. air power to liquidate the threat early, he said.

"We assume that artillery will be a prime target. That is a main duty of the air force," said Azad Miran, chief of KDP military operations.

Chamchamal has been shelled more than once in the decade that Iraq's Kurdish minority has enjoyed self-rule under the protection of U.S. air patrols. But residents said the rumble of the war they heard in Bush's warning in the Azores sounded different.

"We have no special fear of conventional weapons," Jafar said, as nine members of his family waited in the bed of the broken-down Toyota pickup, tucked between clothes, shoes and a carefully arranged television antenna. "But this time we're afraid of the chemicals, because it is the final days of Saddam Hussein."

On a normal day, Chamchamal bustles with traffic in both directions. The border between the Kurdish region and the parts of Iraq still controlled by Baghdad has been porous for years. Taxis, buses and private cars shuttle between the predominantly Kurdish-inhabited cities on both sides of the line, ferrying passengers, jerrycans of gasoline and other goods between the zones.

But today the road was filled with vehicles heading north out of Chamchamal. Kurdish border officials said the traffic from the south nearly stopped last Wednesday, when Iraqi security officials began a crackdown on Kurds inside Kirkuk, the strategic and largely Kurdish city 20 minutes down the four-lane highway.

"The streets and neighborhoods inside Kirkuk look like a war front," said Ali.

Officials and residents said Baghdad fears a popular uprising like the one that wrested control of Kirkuk and many other Iraqi cities from Hussein's government the last time the United States attacked, in the 1991 Persian Gulf War. Baath Party security officials have swept hotels, streets and residents for young Kurdish men who might participate in a rebellion, which Kurdish officials say is being planned.

Travelers carried differing accounts of the Iraqi military posture around Kirkuk, presumed to be a key early target of a U.S.-led invasion. Hussein last month pulled the Republican Guard out of Mosul, another major city in Iraq's northern oil fields. There have been reports he is also drawing down the Republican Guard division in Kirkuk, which would leave both prizes to be defended by the regular army.

At the Kurdish checkpoint, militiamen facing south pointed to a cluster of ragtag rooftops off to the left, pointing out an improvised village called Shorish. Two members of Iraq's regular army showed up there not long ago asking for food, the militiamen said. One wore a shoe on one foot and a boot on the other.

Williams reported from Irbil.