(CNN)Here's a look at Operation Fast and Furious. From 2009-2011, the Phoenix Field Division of the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), along with other partners, allowed illegal gun sales in order to track the sellers and purchasers, who were believed to be connected to Mexican drug cartels.
During the Fast and Furious investigation, nearly 2,000 firearms were illegally purchased for $1.5 million, according to a DOJ inspector General report. Hundreds of guns were later recovered in the United States and Mexico.
October 31, 2009 - Phoenix-based ATF agents get a tip from a local gun shop about suspicious purchases of assault rifles by four individuals. The agents begin investigating whether the individuals were "straw purchasers" working for a large-scale illegal gun trafficking organization. The probe later comes to be known as Operation Fast and Furious.