Most of this comes from the 3 year investigation where they found that the program called Wide Receiver lost control over about 450 guns, not surprisingly, due to bungling. Even US attorneys under Obama couldn't find anybody to indict due to the poorly planned program. The program used tracking devices placed on the guns, which were supposed to be followed after they were sold, however the gunrunners were smarter than they were, they drove in a circle for four hours knowing the planes would then need to refuel, when the planes returned to refuel they made a quick dash across the border. The batteries on the chips they used for tracking devices could only last 36 to 48 hours and their range was limited as their antenna were crushed when they were force fit onto the guns. The agents lost track of the devices because of the limited range, and were never able to regain it during the short period of battery life.
This failure caused the Wide Receiver program to end as none of their goals were met and they did not want to hand any more guns to the cartels. This is a program very unlike the Fast and Furious program that specifically allowed the guns to walk to supposedly "track" them and find the "boss", however they used no tracking devices, no airplanes, and there was never any intention of arresting the straw purchasers or to end this program due to its utter lack of anything resembling a law enforcement program.
There was no way to track the guns after they got over the border, and no attempt to actually make them trackable, even after clearly understanding that particular problem of this program they continued the program regardless understanding that the only place they'd be able to backtrack from was at the scene of crimes. Basically they'd be able to track them back to the program because they were used in murders, and being found at murder scenes has made no helpful notes as to the crime bosses, their locations, or how to catch them.
Today, we know that they were used to murder at least one border patrol agent and an ICE agent. Nobody knows how many of the thousands of weapons they literally let walk over the border have been used to kill Mexicans, nor have they recovered all the weapons used in murders on this side of the border to track them and see if they were part of this program. In Arizona alone over 2,000 guns "walked" and the memos make it clear this happened in at least 5 more states, if they were as prolific it is likely that the leaders of this program let well over 12,000 guns "walk" directly into the hands of ruthless murderers so that they could later find them at the scene of crimes. It appears to many that they wanted to blame US gun laws on the sales and use the "discovery" of so many US guns being used in crimes over in Mexico to add more strict legislation against the sales of guns in the US.
Potential thousands have been murdered using weapons these people chose to intentionally give to Drug Lords and those who traffic in humans on our borders, very often those crossing the border are used as mules for "payment" of their transport. That wasn't Wide Receiver, that was Fast and Furious, that we've since found out Eric Holder lied about when he said he had only found out about it "weeks ago". Memos have surfaced that show him to have lied to Congress yet agents involved in the decisions, who ordered these guns to "walk", have been either laterally moved or promoted, none are under suspension or investigation although it is a clear violation of laws through treaties and even our own laws. This program had no value as a law enforcement program, it is quite literally agents of the US government illegally giving weapons to narco-terrorists who are directly at war with a US ally.
One more amazing fact, in order to get this done they had to have cooperation between agencies. The FBI checks had to be overridden at the very least. This "program", at the very least, goes up to Holder but far more likely the National Security Council due to the inter-agency work that would have had to have been approved.