An investigative task force (named "Langmur" for "Langley murders") was drawn together from both the FBI and local Fairfax County police. They began sifting through recent AK-47 purchases in Maryland and Virginia—there had been at least 1,600 over the previous year alone. Kansi's name was on the sales slip from a gun store in Chantilly, where he had exchanged another gun for the AK-47[1] just three days before the shootings.[2]