(ABC News) -- The gunman who opened fire in a Sikh temple in Oak Creek, Wis., and killed six people has been identified as Wade Michael Page, an Army veteran who left the service with a less than honorable discharge.
Page, 40, served in the Army from April 1992 through October 1998. He was separated from the Army with a less than honorable discharge and had been demoted from sergeant to specialist during his service.
While in the Army Wade served as a sergeant, and later as a specialist based in Ft. Bliss in Texas and at Ft. Bragg in North Carolina. Wade's job was as a Hawk missile system repairman, and he then became a psychological operations specialist, defense official confirmed to ABC news.
Page was shot and killed in an exchange of gunfire with a police officer who sustained "eight or nine" gunshot wounds, authorities confirmed. Officials are treating it as a case of domestic terrorism.
The ex-soldier is believed to the gunman who opened fire on people at the Sikh temple around 10:30 a.m. Sunday morning and killed six people.
SLIDESHOW: Police respond to the scene of a mass shooting at a Wis. Sikh Temple
Police have not given any details on the motive of the shooter, but Bureau of Alcohol, Tobacco, Firearms Special Agent Thomas Ahern said Page had tattoos that suggested he had ties to white supremacists.
"It is being investigated. And what his tattoos signified is being investigated. They are all pieces of a possible puzzle to learn what was his motive in carrying out such a horrific act," Ahern said.
On Sunday the FBI and a bomb squad arrived at a home in Cudahy, Wis., near Oak Creek, and ABC News Milwaukee affiliate WISN reported the action appeared to be related to the temple shootings earlier in the day.
Authorities also were trying to trace a single, semiautomatic handgun recovered at the scene, sources told ABC News.
In addition to the seven confirmed dead, three people -- two adult male civilians and a male police officer -- were in critical condition and were being treated at a local hospital, said officials at Froedtert & The Medical College of Wisconsin.
Page was shot and killed in an exchange of gunfire with the wounded police officer outside the temple and was one of the seven dead.
"The officer stopped a tragic event that could've been a lot worse," Oak Creek Police Chief John Edwards told reporters.
Four people were found dead inside the temple and two others were found dead outside the building.
Edwards said authorities were treating the event as a domestic terrorism incident and the FBI would be conducting a full investigation.
"The FBI is working closely with the Oak Creek Police Department and other local and federal agencies to investigate today's shooting incident," FBI Milwaukee Special Agent in Charge Teresa Carlson said in a written statement. "This remains an active investigation in its early stages. While the FBI is investigating whether this matter might be an act of domestic terrorism, no motive has been determined at this time. We know our community has been deeply impacted by this incident, and our thoughts are with those affected and particularly with the officer who was wounded in the line of duty to protect others."
Individuals attending Sunday services at the Sikh Temple of Wisconsin, just south of Milwaukee, fled in all directions this morning when a gunman entered and began firing. Many hid in bathrooms or other rooms within the temple while the shooter attacked, according to police.
The president of the temple, Satwant Singh Kaleka, was preparing to deliver remarks when he became one of the shooting victims. His son, Amardeep Kaleka, spoke by phone with ABC News' David Muir shortly after getting a call from the priest using his father's phone.
"I picked it up immediately thinking it was my dad, but it was the priest and he was standing right next to him," Kaleka said. "He told me right away that right now my father can't speak. There's too much blood coming out of his back area and we have to get ambulances in there right away."
Soon, he heard briefly from his mother, also in hiding in the temple and asking for information about his father.
For images of the police response and ripples of shock and grief at the scene, click here.
Edwards said 911 calls began pouring into the police department around 10:25 a.m.
The first police officer to respond to the scene, a 20-year veteran on the police force, exchanged gunfire with the suspect and sustained multiple gunshot wounds. He underwent surgery at Froedtert Hospital, the main trauma center in the Milwaukee region, along with two other injured victims.
According to information broadcast over police radio, a witness to the shooting told law enforcement the shooter was a white male, bald, with a heavy build.
Police tactical teams spent more than four hours securing the temple and, at one point, police asked media outlets to stop broadcasting aerial footage from helicopters on television because of tactical operations at the scene. Members of the Sikh community in Milwaukee expressed outrage at the shooting.
"They went to church not knowing that they might die today," said Simran Kaleka, whose family was in the temple, according to ABC News Radio. "I don't know how sick you have to be to do that, and I don't know if it was directed toward the Sikh culture and them having turbans and having beards, but ignorance is not going to get us anywhere."
The wounded president of the temple, Satwant Singh Kaleka, had recently hosted state Rep. Josh Zepnick and the county district attorney to discuss a recent rise in violence against area Sikhs at their stores and businesses, according to the Milwaukee Journal Sentinel.
"It's gut wrenching," Zepnick said today in response to the shooting. "It certainly makes you wonder about how just how far this epidemic of gun violence goes, where innocent people's lives are put at risk in ordinary day-to-day situations. it makes me sick to my stomach."
On Sundays, Sikh temples, called gurudwaras, serve a community meal at which anyone is welcome as part of their community service. The meal, known as a langar, follows the morning services.
The Sikh religion originated in the Punjab region of India.
"Every single member of my family was inside that church," Simran Kaleka said. "No matter who is shot and killed in there, it's going to affect all of us out here because a lot of people are related here. And it's just, for me, my life flashed before my eyes because it's my whole family."
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