The Obama administration Tuesday replaced two senior officials who helped to oversee a troubled federal sting operation that targeted gun trafficking.

The Department of Justice announced that acting Director Kenneth Melson is out at the Bureau of Alcohol, Tobacco, Firearms and Explosives. B. Todd Jones, U.S. attorney for Minnesota, will become acting chief, and Melson was named senior adviser on forensic science in the Office of Legal Policy.

As a seasoned prosecutor and former military judge advocate, U.S. Attorney Jones is a demonstrated leader who brings a wealth of experience to this position, said Attorney General Eric Holder. I will miss working with them, but know that my continued work at the department will contribute in their pursuit and prosecution of violent criminals.

Jones will continue to serve as U.S. attorney while running the ATF, a news release stated.

Additionally, U.S. Attorney for Arizona Dennis Burke has submitted his resignation to President Barack Obama, effective immediately.

Burke and Melson were the top officials with the direct responsibility for overseeing an ATF countertrafficking operation called Fast and Furious, a joint federal law enforcement effort to take down Mexican cartels that were said to be importing U.S.-bought weapons and shipping drugs to the U.S.

The operation is said to have used tactics that allowed suspected smugglers to buy about 2,000 firearms, some of which have turned up in crime scenes on both sides of the U.S.-Mexico border, and many more are unaccounted for, according to The Wall Street Journal.

The operation was also opposed within the ATF, where the usual priority is getting illegal guns off the street.

The New York Times reported that the operation lacked adequate controls, as one purchaser bought more than 600 weapons, agents lost track of hundreds and two guns were recovered at a site in Arizona where a U.S. Border Patrol agent was killed.

The killing led to opposition from bureau agents regarding the operation and they reached out to Congress. Rep. Darrell Issa (R-Calif.), chairman of the House Oversight Committee, and Sen. Charles E. Grassley (R-Iowa) began a congressional investigation into the program.

Today's announcement is an admission by the Obama administration that serious mistakes were made in Operation Fast and Furious, Grassley told The Times, and is a step in the right direction that they are continuing to limit any further damage that people involved in this disastrous strategy can do. We're looking for a full accounting from the Justice Department as to who knew what and when, so we can be sure that this ill-advised strategy never happens again.