A .50-caliber rifle found at Joaquin "El Chapo" Guzman’s hideout in Mexico was funneled through the gun-smuggling investigation known as Fast and Furious, sources confirmed Tuesday to Fox News.

A .50-caliber is a massive rifle that can stop a car or, as it was intended, take down a helicopter.

After the raid on Jan. 8 in the city of Los Mochis that killed five of his men and wounded one Mexican marine, officials found a number of weapons inside the house where Guzman was staying, including the rifle, officials said.

When agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives checked serial numbers of the eight weapons found in his possession, they found one of the two .50-caliber weapons traced back to the ATF program, sources said.

Federal officials told Fox News they are not sure how many of the weapons seized from Guzman’s house actually originated in the U.S. and where they were purchased, but are investigating.

Out of the roughly 2,000 weapons sold through Fast and Furious, 34 were .50-caliber rifles that can take down a helicopter, according to officials.

Federal law enforcement sources told Fox News that ‘El Chapo’ would put his guardsmen on hilltops to be on guard for Mexican police helicopters that would fly through valleys conducting raids. The sole purpose of the guardsmen would be to shoot down those helicopters, sources said.

The Fast and Furious operation involved federal agents allowing criminals to buy guns with the intention of tracking them.

Instead, agents from the ATF lost track of 1,400 of the 2,000 guns involved in the sting operation.

The operation allowed criminals to buy guns in Phoenix-area shops with the intention of tracking them once they made their way into Mexico.

The operation became a major distraction for the Obama administration as Republicans in Congress conducted a series of inquiries into how the Justice Department allowed such an operation to happen.

Former Attorney General Eric Holder was held in contempt after he refused to divulge documents for a congressional investigation into the matter.

This is the third time a weapon from the Fast and Furious program has been found at a high-profile Mexican crime scene. 

William La Jeunesse joined FOX News Channel (FNC) in March 1998 and currently serves as a Los Angeles-based correspondent.