Iraq may have obtained as many as 400 electronic "jammers" that could throw America's smart bombs off their programmed path if the U.S. goes to war, Fox News has learned.

There is "real concern at the highest levels" at the Pentagon that Baghdad may have purchased the jammers from a Russian firm, a senior defense official said.

Fox News obtained exclusive pictures of the jammers from a U.S. military intelligence report.

The Pentagon doesn't know how effective the jammers could be, but they have been known to interrupt a global positioning signal (GPS). That, in turn, could confuse and throw off America's satellite-guided precision weapons.

Officials said that if the smart bombs are diverted from their designated targets, no one knows what, or whom, they might hit instead. The worst-case scenario is they might fall on civilian sites and kill innocent people, causing collateral damage.

That could do great harm to the U.S. effort to garner support for its mission and boost the world's opinion of its actions.

The end result, officials said, could be higher casualty rates on both sides.

One senior defense official said if Iraq does in fact have hundreds of jammers, "it wouldn't stop us from going to war, but things could potentially get messy."

Iraq already may be planning how to make the best use of the jammers. U.S. officials believe a map of Iraq, with Russian writing scrawled on it, may be a diagram of where to place the jammers in order to cause maximum damage and interference with American and coalition bombs.

The types of bombs whose courses may be altered by these jammers are called J-Dams -- for "joint direct attack munitions," guided by global satellites. These are the military's GPS guided bombs. Each one costs about $21,000 and has a maximum range of 15 miles. J-Dams made their combat debut in Kosovo in 1999.

It's estimated that 80 percent of U.S. weapons that would be used in a war with Iraq would be directed via satellites.

The Air Force is now trying to test similar jammers to see if those used by an enemy can really work on U.S. weapons.

War planners "have been working on this problem for quite some time," yet it is only now being made public, Fox News military analyst Lt. Gen Thomas McInerney said Friday afternoon.

He said Russian President Vladimir Putin should look into which Russian firm may have supplied the jammers and should make more of an effort to help the United States make sure they aren't used to the allies' detriment.

U.S. intelligence experts said the jammers are precisely the type of tool Iraqi President Saddam Hussein could use to help turn the world against the United States if President Bush mounts a military attack to oust the dictator.

"Saddam -- what he intends to do is use popular opinion to back him in the Middle East and Europe, wherever he can get it. He doesn’t mind sacrificing civilians," former CIA officer Robert Baer told Fox News Friday. "He did it during the Gulf War and he’s going to do it again."

Baer said if Saddam has the opportunity to use the jammers, he will draw the military into the cities -- since military targets are usually the first targets in war time. Saddam can then use the jammers so that U.S. and allied bombs are thrown off course and have the potential to hit schools, hospitals or homes in populated areas.

And Saddam would be certain to make sure that the whole thing is televised, Baer said, so he can show the world the human toll caused by U.S. bombs.

"It’s going to have a ripple effect all throughout the Middle East, which he’s counting on," Baer said.

Fox News' Bret Baier and Molly Henneberg contributed to this report.