68K guns seized in Mexico traced to U.S. WASHINGTON, April 27 (UPI) -- More than 68,000 guns seized by Mexican authorities from 2007 to 2011 have been traced to the United States, U.S. officials said. The U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives said in a news release the guns had been manufactured in the United States or legally imported into the United States by a federal firearms licensee. All the guns were suspected of being used in crimes in Mexico. The guns were among more than 99,000 the Mexican government submitted to ATF for tracking, the release said. During the five-year span, ATF said the proportion of pistols had declined from 44.9 percent of seizures in 2007 to 38 percent in 2011 while the proportion of rifles seized climbed from 28.2 percent to 43.3 percent. The Christian Science Monitor has reported at least 50,000 people are estimated to have died in organized crime-related killings since 2006 in Mexico, which has been beset by drug cartel violence.