The Scottsdale police officer who shot and killed a man holding a baby Tuesday has been involved in seven shootings since 2002, six of them fatal, police said Wednesday.

Officer James Peters shot 50-year-old John Loxas on Tuesday evening after police were called to a house in the 7700 block of East Garfield Street, near Hayden and McKellips roads. Neighbors had called 911 earlier and said Loxas had threatened them with a handgun.

Peters, a former member of the department's SWAT team, was one of six officers who responded to the call. The 12-year police veteran is on administrative leave, which is standard after any police shooting, said Sgt. Mark Clark, a Scottsdale police spokesman.

According to the 911 call, the neighbors said Loxas was pushing his 9-month-old grandsonin a stroller and walked over and kicked a neighbor's trash can into the street. When another neighbor went to pick it up, Loxas returned with the baby in his arms and started yelling, "You got a problem with that?" the caller tells the dispatcher. "The guy pulls out a gun, cocks it and aimed it at him."

When officers arrived, Loxas had returned to his house, but came to the door with the baby in his arms, police said. Peters and another officer told investigators that they saw a black object in Loxas' hand. Loxas turned to go back inside when Peters, who was standing 18 feet away at the edge of the driveway, shot him in the head with his patrol rifle, police said.

"(Loxas) was holding the baby in his left arm in front of his upper body and face. Moments later, he reached down to his right, lowering the baby, clearly exposing his head and upper body. Officer Peters responded to the movement with a single shot (to) the suspect's head. The suspect fell to the ground and the baby was rescued by officers. The suspect died instantly," Clark said.

Peters "felt he had to prevent him from re-entering the house," Clark said. "The intent was to rescue the baby." Investigators later determined that Loxas was not carrying a gun but had a cellphone in his pants pocket.

A search warrant recovered a loaded pistol "a few feet from where the suspect fell inside the residence," Clark said. "It was wedged between the arm and cushion of a chair a few feet away from where he fell." It is the same pistol believed to have been used to threaten neighbors, he said. A loaded shotgun also was found near a chair a few feet from the pistol, Clark said. In addition, police found at least eight "Airsoft" type rifles and pistols, as well as "a functional improvised explosive device," he said.

Loxas lived in the house alone and babysat his grandson often, police said. The home was filled with garbage and clutter and a city inspector determined the home to be uninhabitable Wednesday, Clark said.

In 2010, Scottsdale police were called to the house because Loxas was threatening neighbors with a pistol, police said. He has been arrested at least once, police said. The 911 caller told the dispatcher that this wasn't the first time that Loxas had pointed a gun at neighbors.

On Wednesday, several neighbors said that house parties were frequently held at the man's home, often lasting until 3 a.m. or later. Residents of two nearby homes said they had filed noise complaints with police.

Scottsdale police Chief Alan Rodbell said he is confident that the external review by legal experts will "leave the community with the same sense of confidence that I have in my officers, my detectives and oversight in this very serious incident."

Lyle Mann, executive director of the Arizona Peace Officers and Training Board, a state law enforcement panel, said that he couldn't comment specifically about Peters, because he didn't know the circumstances of the seven shootings. But he said "some are functions of assignment."

"If you are out chasing armed felons every day, there's the probability that they're going to be bad people. While it feels like it clearly is an anomaly in terms of this person being involved in this many discharges, I wouldn't read anything into that," Mann said.

Each of Peters' previous shootings have been determined justified through an internal investigation as well as an external investigation by the Maricopa County Attorney's Office.

Peters' previous fatal shooting occurred in March 2010, when Peters shot and killed a man suspected in a string of bank robberies. At the time, The Republic reported that the city had settled in 2009 with the family of one of the people involved in a different fatal shooting for $75,000 but denied liability.

In another case, Peters was honored for his actions in responding to a hostage situation and the hostage thanked the officer for saving his life and shooting the suspect.

Peters also was involved in these previous shooting incidents, police confirmed:

Nov. 3, 2002: Peters was one of three SWAT officers who fired at Albert Redford after a nearly four-hour standoff at his north Scottsdale home. Officers had been called out for a report of domestic violence. Officers fired a total of seven shots, striking Redford three times.

March 25, 2003: Peters shot and killed disbarred lawyer Brent Bradshaw, 47, of Scottsdale. Officers responded to shotgun blasts at Bradshaw's home. Three hours later, police found Bradshaw wandering along the Arizona Canal at Miller and Chaparral roads, carrying a shotgun. Officers tried unsuccessfully to get him to put down the gun.

Oct. 10, 2005: Peters shot and killed Mark Wesley Smith, a burglary suspect, during a confrontation outside an auto-body shop near Hayden and McKellips roads. Smith was smashing car windows in a rage outside the body shop. Autopsy reports would later show that he was high on methamphetamine.

April 23, 2006: Peters shot and killed Brian Daniel Brown, 28, who took a Safeway employee hostage after he hijacked a Krispy Kreme delivery truck in Peoria. Peters received a Medal of Valor for this incident in June 2007.

Aug. 30, 2006: Peters and Officer Tom Myers fatally shot Kevin Hutchings after Hutchings fired at least one round at police outside his northeast Mesa home. Scottsdale police were trying to contact Hutchings about a Scottsdale assault earlier that evening with a longtime acquaintance of Hutchings. Hutchings' family sued the city and eventually settled out of court for the $75,000, city officials said.

Feb. 17, 2010, Peters and Scottsdale Detective Scott Galbraith shot Jimmy Hammack Jr., 46, after Hammack drove his truck toward detectives who were investigating him as a suspect in three Scottsdale bank robberies and two in Phoenix. Hammack later died from his injuries.

This is the second time in less than three weeks that a Scottsdale police officer shot and killed a man.

On Jan. 28, Jason Edward Prostrollo, 25, was shot dead after officers were called to the north Scottsdale home of Prostrollo's acquaintances. Police were called in the early morning by a 35-year-old woman saying Prostrollo, a guest in her home, was drunk and fighting with her 50-year-old boyfriend, and had a knife.

Prostrollo, a former Marine with two tours of duties in Iraq, came out of the house with pieces of a pool cue in each hand, police said. He ignored commands to drop the cues and stop walking, police said. A K-9 officer released his dog and a bite from the dog didn't deter Prostrollo, who kept walking toward officers. That's when Lt. Ron Bayne shot Prostrollo and killed him.

Prostrollo's family and friends have questioned the police department's use of lethal force.

Reporter John Genovese contributed to this article.