Police Probe If Same Gunman Responsible For 3 Different Murders PHOENIX - Authorities are investigating whether a sheriff's deputy shot to death while answering a burglary call and a New Hampshire couple found dead in their car in Arizona were killed by the same gunman. Deputy William Coleman, 50, was gunned down early Sunday at a north Phoenix medical building. A man got out of a van and opened fire, striking Coleman under his bulletproof vest, Maricopa County Sheriff Joe Arpaio said. The suspect was shot and killed by other deputies. The Arizona Republic reported that Coleman and the couple near the resort town of Sedona on Friday were all shot with a high-powered rifle. And the two crime scenes are connected by Interstate 17. The theory that the two shootings may be the work of the same gunman could explain why the man decided to open fire on the deputies, Deputy Jeffrey Sprong, a spokesman for the Maricopa County Sheriff's Office, told the Republic. "That (a connection) is definitely something our investigators will look into," Sprong said. It wouldn't surprise me if it turned out to be the same guy. Yavapai County sheriff's officials says they're comparing evidence with Maricopa County investigators and expect to have results sometime Monday. Members of a Jeep club found James Johnson of Jaffrey, N.H., and Carol Raynsford of Nelson, N.H. in their red older-model Subaru sedan at a remote turnout on Arizona 89A on Friday morning. Someone shot them with a .223-caliber rifle while they were parked on a highway turnout, Yavapai County sheriff's spokesman Dwight D'Evelyn said. Detectives found numerous casings from the rifle on both sides of the car. "It doesn't appear it was provoked in any way, that's what makes it so unusual and baffling for our detectives," he said. D'Evelyn said Johnson and Raynsford were not married but he did not know if they were romantically involved or just friends. The couple were apparently vacationing in the area and detectives are trying to trace their travels. Authorities have posted a reward and are asking anyone with information to call the sheriff's office or the county's Silent Witness program. Deputies aren't sure when Johnson and Raynsford were killed, D'Evelyn said. Some callers reported seeing the car parked at the turnout on Thursday, and detectives are using receipts and other items found inside the vehicle to try to trace their steps and establish a timeline. Coleman was a 20-year veteran. He is survived by a wife and two young children, ages 4 and 7, Arpaio said. He also has grown children in another state. Coleman was assigned as a patrol deputy but had previously worked the sheriff's lake patrol unit.