As desperation grew among the thousands of Iraqi Kurds massed at the border, a refugee was killed when Turkish security forces fired in the air to stop 2,000 Iraqis from marching to protest lack of food and aid, a newspaper reported Thursday.

The report came as the regional governor of southeastern Turkey, Hayri Kozakcioglu, said the number of refugees at the border had swelled to 400,000.A Kurdish rebel spokesman in London, meanwhile, said that Iraqi troops had launched a major offensive against the guerrillas inside an area of northern Iraq being protected by U.S. forces.

"Iraqi troops supported by artillery, tanks and helicopter gunships attacked our guerrilla positions north of Salahuddin," said Hoshyar Zebari, spokesman for the Kurdistan Democratic Party.

Zebari noted the reported Iraqi attack came north of the 36th parallel, in the area the United States has defined as a protective zone for fleeing Kurds.

Associated Press reporter Alex Efty, who was taken to the scene of a battle between Kurds and Iraqi soldiers Thursday in the village of Kore, near Salahuddin, said the rebels told him the soldiers did not use helicopters because of a U.S. warning not to do so.

Also Thursday, hours before a permanent cease-fire was to be signed in the gulf war, some U.S. National Guard medical units were being diverted to Turkey to help the Kurdish refugees.

And U.S. AWACS surveillance planes and fighter-bombers were in the air over Iraq to back up the warning from the Bush administration not to threaten the refugees or interfere with the airdrop of supplies.

The reported protest Wednesday night reflected the worsening plight of the refugees. Many have been sleeping outside in rainy, near-freezing weather for days without adequate food, water and medicine, despite an international outpouring of aid.

Exposure is finishing off many who survived the flight over rugged mountains from Saddam Hussein's forces.

According to the reliable daily Cumhuriyet, the 2,000 refugees were trying to march from a camp in the remote border city of Cukurca, 35 miles east of here, to the town center.

Security forces opened fire in the air to stop them, and one refugee was killed and two wounded, the newspaper said. There have been numerous cases of refugees being shot while Turkish troops, sometimes firing wildly, were attempting to keep order.

Thirty-seven people died from exposure or illness at the Cukurca camp on Wednesday night, 27 of them children, the Anatolia news agency reported.

There are no comprehensive figures on the number who have died in the makeshift Turkish camps. But doctors say scores of people are succumbing each day to diarrhea and the effects of exposure.

At a camp in the Uzumlu area, west of Cukurca, the estimated 50,000 refugees had only one doctor - himself a refugee - while two Turkish medics were away looking for supplies.

"In two or three days, thousands of children will die of gastroenteritis and pneumonia," predicted the doctor, Maj. Sadi Sadeq al-Maruyyati, who fled with his family.

"If I return to Iraq, Saddam will kill me and my family. If I live here, I will get killed by malnutrition, cold and disease," he said.

Al-Maruyyati said about 1,000 adult refugees at Uzumlu had succumbed to cold and disease since their arrival and 20 children were dying every day.

As many as 2 million Kurds - about half the ethnic group's population in Iraq - have been seeking refuge along the border with Iran and Turkey.

They left entire cities nearly deserted as they fled, fearing reprisal after a failed Kurdish uprising that sought to capitalize on Baghdad's defeat in the war over Kuwait.

Iran and Turkey have been overwhelmed by the human wave, and international relief officials say air drops by the United States, Britain and France are barely making a dent, coming too late for many refugees. Vehicles trying to reach the area have been slowed by muddy, narrow roads.