Attorney General Kelly Ayotte said Liko Kenney shot Cpl. Bruce McKay four times, then ran over him with his car after a traffic stop Friday night.
Gregory Floyd, who was driving by with his son, grabbed Mc- Kay's gun, then shot the 24-year- old Kenney when he refused to put his gun down, Ayotte said.
"This once again reminds of us of the difficult and dangerous work that is done everyday by the law enforcement of this state to protect each of us," Ayotte said at a news conference in Concord.
Authorities said McKay pulled Kenney over for speeding on Route 116. Kenney then took off, and McKay pursued him for about 1Â½ miles before pulling his cruiser in front of Kenney's car and pushing it off the road.
The officer used pepper-spray on Kenney and his passenger then turned around, Ayotte said. That's when he was shot.
"Cpl. McKay's cruiser video confirmed for police investigating this case that in fact Mr. Kenney had discharged several shots at Cpl. McKay before running him over," Ayotte said.
Soon after, Floyd arrived and confronted Kenney while his son, also named Gregory Floyd, called for help using the officer's radio. Authorities have determined that his actions in shooting Kenney were justified.
An autopsy showed McKay died of four gunshot wounds. Autopsy results on Kenney were incomplete Saturday.
The 48-year-old McKay was a 12-year veteran of the Franconia Police Department and previously had worked in Haverhill. Survivors include a daughter, Ayotte said.
"It really tears at the fabric of the community and the fabric of the state," said Gov. John Lynch, who visited the town of about 900 residents Saturday. People paid their respects at the local police station, bringing flowers.
Ayotte said McKay had "prior dealings" with Kenney, who was convicted of assaulting the officer and resisting arrest in 2003. Kenney's uncle said the animosity between them was so great that if Kenney got pulled over by McKay, "he had the right to request a different officer."
"That's what I heard, that Liko requested a backup officer and that was when he was pepper- sprayed," said Bode Miller's father, Woody Miller.
The passenger in Kenney's car told police Kenney said something like, "Get another officer" just before speeding off after the initial stop, Ayotte said.
"But he refused to produce a license and registration to Cpl. McKay, which is standard operating procedure, and then just took off. So this is a situation where he obviously disobeyed a police officer," she said.
Woody Miller said his nephew claimed the officer once beat him during an arrest.
"They had a long relationship," said Miller, who operates an international tennis camp in nearby Easton. "There's been physical altercations between them before in the course of being arrested."
Bill Kenney, another uncle, agreed. "They had it in for each other."
Woody Miller said he last saw his nephew Friday morning, when Liko Kenney was on his way to work. He was running late, but he was in good spirits.
Miller said Kenney, who lived next door to him, didn't have a steady job, but often took work cutting firewood and picking fiddlehead ferns, a wild green that grows in the region and is considered a delicacy.
Bode Miller, who had bailed his cousin out of jail once, was on his way home to Franconia, his father said. In 2005, Bode Miller was fined $250 for going 83 mph in a 40 mph zone in his hometown of Franconia. According to an article published on Sports Illustrated's Web site, SI.com, Miller said he chose to contest the ticket "to try to get my fine reduced and to antagonize McKay."
Lynch ordered all state flags be flown at half-staff in memory of the officer. Franconia's Board of Selectmen released a statement saying that the town "mourns the tragedy that befell our community on the evening of May 11. ... We ask that you all embrace in your thoughts and feelings the families affected by this tragic incident."
It's the second time in less than a year that a New Hampshire police officer has been killed on the job. In October, when Manchester Officer Michael Briggs was shot in the head while investigating reports of gunshots in an alley. Michael Addison is charged with capital murder in the shooting.