It has been reported that the top U. S. military officer refused Sunday to say whether giving sensitive Afghan war documents to WikiLeaks constitutes treason.

"I'll let the investigation run its course, and we'll see where it goes, specifically. But the concern, obviously, is for the leaking of classified information that is going to endanger people, operations and potentially, depending on how serious it is, outcomes" in the war, Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, said, when asked on NBC's "Meet the Press" whether the leak of at least 75,000 documents to the whistle-blower Web site was treason.

Troops are put in danger because the Taliban "would look at what our tactics are, how we report, where we're fighting, who's involved ... the kinds of things that we do. And yet ... the volume is such that we really haven't put it all together to be able to say this is exactly what the potential is in terms of that," said Mullen.

A U. S. soldier in Iraq, charged in May with leaking a video to WikiLeaks of an attack that killed 12 people, faces additional charges, officials last week.

The Defense Department has said that Army Pfc. Bradley Manning, 22, was formally charged with unauthorized uploading of classified information to his computer and sharing it with unauthorized people.

It was further reported that Mullen refused to comment on the details of that investigation. (With Inputs from Agencies)