It has not been a good week for the Pentagon. Fresh charges of botched raids and innocent civilians killed or mistreated have taken center stage in the latest reporting on the war in Afghanistan. How are defense officials reacting?

It has been an unusually mild winter in Washington. But at the Pentagon, "snowflakes" are falling - "snowflakes" in this case being the nickname for short, handwritten notes from the defense secretary asking for information on this-or-that. These days, Pentagon sources say the "snowflakes" from Donald Rumsfeld have been seeking data on the latest allegations of U.S. military mistakes in Afghanistan.

There have recently been a succession of such charges involving botched raids, innocent civilians killed and others beaten.

Pentagon officials are quick to point out that none of the allegations have been proven to be true.

Yet they say it is disheartening to even hear of such claims, especially in light of what they view as an otherwise successful anti-terrorism campaign in Afghanistan.

But Defense Secretary Donald Rumsfeld and other top officials are now taking tough questions from reporters at news briefings.

"Are you worried that this is turning into some kind of public relations disaster where the headlines in the newspapers, the preponderance of them, are on mistakes rather than accomplishments?" one reporter asked Mr. Rumsfeld.

Publicly, Mr. Rumsfeld does not appear to be visibly upset by the scrutiny. But he says the investigations now under way reflect the military's concern.

"Any time there is a suggestion that U.S. forces have, as you characterized it, made a mistake, it is something that we take very seriously as a country, and certainly the armed forces and the Pentagon do. When that occurs, we ask the appropriate people to undertake an investigation and to look into the charges or the allegations that have been made. We do that because we care that things be done as well as it's humanly possible to do them," Mr. Rumsfeld says.

Mr. Rumsfeld and others try to shift reporters' attention to the good they say the United States has done in Afghanistan - like ridding the country of the repressive Taleban leadership and providing humanitarian assistance.

But Pentagon officials contend the news media do not appear to be terribly interested in stories about aid shipments.

They also say U.S. troops in Afghanistan are still involved in operations that are secret and therefore invisible.

General Richard Myers, chairman of the military's Joint Chiefs says talking openly, for example, about U.S. successes in hunting down fugitive al-Qaida or Taleban leaders could harm ongoing operations.

"We are anxious to share some of these successes with you. The problem is that once you do that, then the tactics and the techniques and the procedures that are being used in this very difficult mission of locating leadership and other pockets of al-Qaida or Taleban, once we tell you how successful we've been, then we reveal those tactics, techniques and procedures, and sometimes they're easy to thwart. So that's why we have to be very careful," he says.

Some Pentagon sources believe there is a simple explanation behind the latest spate of claims of innocent civilians killed or beaten: money.

Having heard of cash hand-outs apparently orchestrated by the Central Intelligence Agency to families of the victims of one U.S. raid north of Kandahar, other Afghans may be coming forth now with tales designed to win not just sympathy but cash.

One Pentagon official calls the alleged CIA payments a bad idea and says they may have opened a Pandora's box of claims. This official says the military has to look into them, but he says determining the truth is often a difficult prospect in a place like Afghanistan.

The official also says that innocent people, regrettably, always get caught in the crossfire and killed in wars. No matter how accurate and careful - and U.S. forces, he says, have never been more accurate or more careful - war cannot be free of civilian casualties.