The Myth of 90 Percent: Only a Small Fraction of Guns in Mexico Come From U.S.

There's just one problem with the 90 percent "statistic" and it's a big one: It's just not true.

In fact, it's not even close. The fact is, only 17 percent of guns found at Mexican crime scenes have been traced to the U.S.

What's true, an ATF spokeswoman told FOXNews.com, in a clarification of the statistic used by her own agency's assistant director, "is that over 90 percent of the traced firearms originate from the U.S."

But a large percentage of the guns recovered in Mexico do not get sent back to the U.S. for tracing, because it is obvious from their markings that they do not come from the U.S.