5 Things You Didn't Know About Operation Fast and Furious

Sept. 30, 2012— -- The U.S. government's botched Fast and Furious gun-trafficking operation left a trail of bullets and bodies in Mexico. In a special investigation by Univision News, which aired Sunday night, several new revelations came to light. Here are five worth knowing.

1. Fast and Furious Guns Used in Infamous Massacre

Mexican military reports show that at least three guns from North America were used in the Salvarcar massacre in 2010. A total of 15 people died in that incident, most of them teens. They were gunned down by the Juarez cartel, which mistook the group for rival Sinaloa cartel members. According to one document, the weapons entered Mexico illegally through a border point near Columbus, New Mexico.

2. 57 Previously Unidentified Weapons Surface

Univision cross-referenced the serial numbers off guns used in Fast and Furious against guns seized in Mexico. Nearly 100 of those weapons were used in crimes, and 57 of them were not mentioned in an investigation carried out by the U.S. Congress.

3. Mexico Knew About Fast and Furious

Andrew Selee, vice president for programs at the Woodrow Wilson Center in Washington D.C. says the Mexican government was aware of the gun-walking, in spite of releasing a statement saying they were not. William Newell, the special agent in charge of ATF's Phoenix field division and one of the supervisors of Fast and Furious, told Univision, via his attorney, that the Procuraduria General De La Republica (PGR) in Mexico was certainly aware of the operation.

4. U.S. Gun-Walking Operations Extended to Other Countries

Fast and Furious was not the only ATF operation of its kind that went awry. In Operation Castaway, Hugh Crumpler, a former ATF informant, told Univision News the ATF deliberately allowed guns to pass into Honduras, Puerto Rico and Colombia. Several of those weapons have already been found at crime scenes and in the hands of local cartels. In an email message, the ATF claims that they "found out about the weapons when they had already been shipped."

5. U.S. Agents Were Attacked with U.S. Weapons

Victor Avila and Jaime Zapata, two U.S. Federal Agents assigned to the U.S. Embassy in Mexico, were in the process of transporting surveillance equipment when their vehicle was surrounded by cartel members and shot more than 90 times. Zapata died and Avila was seriously wounded.

Prior to traveling into the region, Avila reached out to a supervisor expressing concerns over security that were backed by a U.S. State Department document which forbade U.S. Embassy employees from traveling in that area. The reason: It was heavily controlled by the Zetas cartel. According to an exclusive interview with Avila, the supervisor did not share his concerns. Three of the guns used in this shootout were also from a gun-walking operation, but not Fast and Furious.

Families for both agents say they still do not understand why the agents were asked to transport equipment through this region, or why the men who trafficked these weapons were not arrested months earlier.