A 65-year-old grandfather was gunned down overnight while out for a walk in his Loveland, Colorado, neighborhood, sparking fear that a serial shooter might be on the loose in the area, after a bicyclist recently was killed and a driver wounded nearby Police and the FBI have refused to comment on whether a sniper is on the prowl in the Loveland area. But they offered a $10,000 reward for information in the first two unsolved shootings, which authorities say are related — though they haven’t said how. In one case, John Jacoby, 48, was riding his bike May 18 on a rural road in Windsor when he was shot twice. A passing motorist later discovered his lifeless body. In the other, Cori Romero, 21, driving on Interstate 25 on April 22 was shot in the neck but survived. All three shootings happened within 15 miles of each other. Officials say at this stage in the investigation it is too early to know if the latest one, in Loveland, is connected.