The sniper shooting of a 72-year-old Washington, D.C. man has been linked to five earlier shooting deaths in nearby Montgomery County, Maryland, and police said on Friday that the same high-powered rifle was used in at least four of the killings. "This evening the forensic laboratory linked the projectile from the D.C. shooting to three of the shootings that occurred in Montgomery County. As a result of that, they're able to tell now that four shootings were done from the same firearm," said Michael Bouchard, a special agent for the Bureau of Alcohol, Tobacco and Firearms. Tests on the slugs removed from the other two victims in Maryland were not yet complete.