Since early last week, when refugees in Jordan first reported seeing dead civilians and smoldering autos along a highway in western Iraq, claims of U.S. and allied bombing of Iraqi civilians have increasingly been reported in televised scenes approved by Iraqi government censors.

Vivid images on Cable News Network of injured children, flattened homes, and weeping families in towns such as Diwaniyeh, south of Baghdad, have raised concerns in Jordan and elsewhere in the Arab world that the massive U.S. and allied aerial bombardment is harming noncombatants.

U.S. military officials at daily press briefings have found themselves increasingly pressed to talk about civilian casualties in a bombing campaign that so far has involved the dropping of tens of thousands of tons of explosives in more than 18,500 sorties by combat aircraft.

Is the war for Kuwait slowly destroying Iraq and its citizens, not just its military forces, contrary to the repeated pledges of U.S. officials from President Bush on down?

While the continuing violence of the war prevents a direct, independent examination, preliminary speculation by U.S. officials and a few independent experts is that U.S. munitions have not caused surprising or untoward civilian damage, and appear to be hitting far fewer noncombatants than orchestrated bombing in previous wars.

At the same time, officials and experts say, the destruction caused by bombs that missed their targets surely exceeds what U.S. officials have led the public to expect by televising scenes of precision-guided weapons hitting the doors of munitions dumps or flying down the air shafts of confirmed missile warehouses, while leaving neighboring buildings unscathed.

As of early last week, Iraq officially estimated that the bombardment had caused 320 civilian deaths and 400 injuries, including women and children. They also charged that religious sites, a museum, food warehouses and a civilian train were among the targets.

Several experts on air warfare said the Iraqi number was surprisingly low, given the massive quantity of munitions used on strategic targets in and around major Iraqi cities since the war began. "If they are accurate, this bombing campaign is producing fewer casualties than any previous bombing campaign in history," said Robert Pape Jr., a research fellow at the University of Michigan Center for International Peace and Security.

A U.S. military official, who spoke on condition that he not be identified, said current, informal Pentagon estimates also are that several hundred Iraqi civilians may have perished in accidental bombings. But some officials cautioned that neither the Iraqis nor U.S. military forces may know the true magnitude of civilian casualties until after the war is over.

Maj. Gen. Robert Johnston, chief of staff for U.S. Central Command, yesterday responded to the latest questions on the subject from the press by reiterating "with total conviction that we are scrupulously avoiding civilian targets. . . . That's not to say that there will not be some modest collateral damage and I would not stand here and say there will not be one single civilian casualty."

Nevertheless, no military official in the first 17 days of the war has acknowledged or described publicly a single incident in which U.S. weapons have mistakenly hit civilians in Kuwait or Iraq. Military officials have also declined to provide public estimates of the number of Iraqis killed to date or expected to die in combat in coming weeks.

"We did that during {the} Vietnam {conflict}. That was a mistake," Johnston said. "Our ability to count, to give you a body count, is so imprecise that it's not a good way of measuring an enemy engagement." Brig. Gen. Pat Stevens, the Central Command deputy director of logistics, said Thursday that such numbers also were susceptible to manipulation by "people {in combat} who are trying to achieve results for very good reasons."

The principal reason U.S. officials say they have omitted any mention of specific bombing accidents is to avoid inflaming Arab concerns that Western-led military forces are assaulting Iraq's Moslem population. The political dangers were demonstrated when Jordanian Foreign Minister Taher Masri and Prime Minister Mudar Badran denounced last week's air attacks on what they said were civilian trucks and cars on an Iraqi highway near their border.

Masri said the attacks were deliberate and had violated the Geneva Conventions of the International Red Cross, which prohibit "the destruction of property if not necessitated by military operations." Other Jordanian politicians described the raids as brutal and racist.

Lt. Gen. Thomas Kelly, operations director for the Joint Chiefs of Staff, yesterday gave his most forthcoming explanation for the raids after being questioned for several days. "We have been operating in that area," he said, adding that it is near the launching sites for Scud missiles aimed at Israel.

Explaining how an accident might have occurred, without disclosing that one did, Kelly said, "It's difficult to look at the ground and tell what a civilian target is and what a military target is, because, for example, oil trucks out in that area could be carrying fuel for Iraqi {military} aircraft," Scud missiles or illegal export.

"A lot of these operations have been taking place at night" when poor weather obstructs pilot vision, Kelly said. "If a truck chooses to operate in that environment, there is some risk." He added, "We're not purposely going after civilian vehicles. {But} if one got hit, it was certainly by mistake."

Kelly, like the Joint Chiefs of Staff chairman, Gen. Colin L. Powell, is said to have been scarred by the controversy over the civilian deaths during the December 1989 U.S. invasion of Panama. Americas Watch, the human rights monitoring group, charged the military with violating the Geneva conventions by failing to adequately protect civilians in the slums of El Chorillo, near the heavily attacked Panamanian military headquarters.

Many military officials remember the criticism that followed the accidental U.S. bombing of residential areas of Libya during a 1986 retaliatory raid for the terrorist destruction of a discotheque in West Berlin that was frequented by U.S. servicemen. They also recall the controversy over B-52 bombing raids in Vietnam that were estimated to have killed at least 52,000 civilians.

Pape said that by his rough estimates, a civilian was killed for every four tons of bombs dropped to support the invasion of Normandy during World War II, a conflict where large cities were routinely targeted in deliberate campaigns of civilian intimidation. He said that in contrast, roughly one civilian was killed for every 15 tons dropped during the Vietnam bombing raids in 1972.

U.S. officials have repeatedly declined to disclose the cumulative tonnage of explosives dropped on Iraq, although one source said he understood that 2,200 tons were dropped on Jan. 17, the first day of the war. Pape said that taking the Iraqi death estimate and assuming that an average of 5,000 to 7,000 tons of explosives are now being dropped in much larger raids, a civilian has been killed for every 200 tons of explosive dropped.

If this calculation is correct, what Pape called a comparatively low rate of civilian deaths would be the result of extensive use of precision-guided munitions and improved aircraft navigation. Officials also say some Iraqi deaths and damage may be due to Iraqi antiaircraft fire that returns to earth.

"Given that thousands of bombs are being used on a daily basis, a civilian can very easily be in the wrong place at the wrong time," Pape said. "The danger is that expectations may have been raised to the point where the public expects '0' accidental losses, while in war, accidents happen all the time."

Baghdad Radio said yesterday that there have been 18 "cowardly" raids on residential areas, but did not make clear whether that meant Baghdad alone. CNN showed extensive footage from Diwaniyeh of what appeared to be bombed apartment houses and shops, with no apparent signs of any military targets.

Earlier this week, CNN showed footage of U.S. sea-launched cruise missiles that appeared to hit strictly residential targets around Baghdad. U.S. officials said the weapons were aimed at airfields, and may have gone off course by themselves or been deflected by Iraqi antiaircraft fire.

More than 280 of the cruise missiles have been fired to date, and at least a few can be expected to malfunction, several officials said.

"What we're seeing coming out of Baghdad is coming from a controlled environment," Kelly said. "We don't have a free press there that can act as a check on the people who took the pictures. . . . I will guarantee you that if a mistake was made, it was made in the vicinity of a military target."