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Wade Michael Page strode into the temple carrying a 9mm handgun and multiple magazines of ammunition and opened fire without saying a word, authorities said.
When the shooting at the Sikh Temple of Wisconsin in suburban Milwaukee ended, six victims ranging in age from 39 to 84 years old lay dead. Three others were critically wounded.
Page, who joined the Army in 1992 and was discharged in 1998, was described by the Southern Poverty Law Center as a "frustrated neo-Nazi" who was active in the obscure underworld of white supremacist music.
Mark Potok, a senior fellow at the nonprofit civil rights organization in Montgomery, Ala., said Page had been on the white-power music scene for more than a decade, playing in bands known as Definite Hate and End Apathy.
"The name of the band seems to reflect what he went out and actually did," said Potok. The music often includes lyrics that discuss genocide against Jews and other minorities.
In a 2010 interview, Page told a white supremacist website that he became active in white-power music in 2000, when he left his native Colorado and started the band End Apathy in 2005.
He told the website his "inspiration was based on frustration that we have the potential to accomplish so much more as individuals and a society in whole," according to the law center. He did not mention violence.
End Apathy's MySpace page said the group was based in Nashville, N.C.
Joseph Rackley of Nashville, N.C., said Monday that Page lived with his son for about six months last year in a house on Rackley's property. Wade was bald and had tattoos all over his arms, Rackley said, but he doesn't remember what they depicted. He said he wasn't aware of any ties Page had to white supremacists.
"I'm not a nosy kind of guy," Rackley said. "When he stayed with my son, I don't even know if Wade played music. But my son plays alternative music, and periodically I'd have to call them because I could hear more than I wanted to hear."
Page joined the military in Milwaukee in 1992 and was a repairman for the Hawk missile system before switching jobs to become one of the Army's psychological operations specialists assigned to a battalion at Fort Bragg, N.C.
As a psyops specialist, Page would have trained to host public meetings between locals and American forces, use leaflet campaigns in a conflict zone or use loudspeakers to communicate with enemy soldiers.
He never deployed overseas while serving in that role, Pentagon spokesman George Wright said.
Page was demoted in June 1998 for getting drunk while on duty and going AWOL, two defense officials said, speaking on condition of anonymity because they were not authorized to release information about the gunman.
Page also received extra duty and was fined. The defense officials said they had no other details about the incident, such as how long Page was gone or whether he turned himself in.
Online records show Page had a brief criminal history in other states, including pleading guilty to misdemeanor criminal mischief after a 1994 arrest in El Paso. He received six months' probation. Page also pleaded guilty to driving under the influence in Colorado in 1999 but never completed a sentence that included alcohol treatment, records show.
Suburban Milwaukee police had no contact with Page before Sunday's shooting, and his record gave no indication he was capable of such violence, authorities said.
The FBI was leading the investigation because the shooting was considered domestic terrorism, or an attack that originated inside the U.S. The agency said it had no reason to believe anyone other than Page was involved.
Page began shooting as several dozen people prepared for Sunday services.
Satpal Kaleka, wife of the temple's president, Satwant Singh Kaleka, was in the front room and saw the gunman enter the temple, according to Harpreet Singh, their nephew.
"He did not speak. He just began shooting," said Singh, relaying a description of the attack from Satpal Kaleka.
Kaleka said the 6-foot bald white man - who worshippers said they had never seen before - seemed like he knew where he was going.
"We never thought this could happen to our community," said Devendar Nagra of Mount Pleasant, whose sister escaped injury by hiding as the gunman fired in the temple's kitchen. "We never did anything wrong to anyone."
Federal officials said the gun used in the attack had been legally purchased.
Page was issued five pistol-purchase permits in 2008 by the Cumberland County Sheriff's office in North Carolina, paying a $5 fee for each. The sheriff's office declined to release his application form, which requires another person to affirm the applicant is of "good moral character." The forms also typically ask about military experience of applicants, who must pass a criminal background check.
Page did not have the additional permit needed to legally carry a concealed weapon.
On Sunday, the first officer to respond was shot eight to nine times as the officer tended to a victim outside. A second officer then exchanged gunfire with the suspect, who was fatally shot.
The wounded officer was in critical condition Monday, along with two other people who were wounded.
Balginder Khattra of Oak Creek, said Monday that his 84-year-old father, Suveg Singh Khattra, was among the dead. Khattra says his father didn't speak English but loved living in America.
Sikhism is a monotheistic faith founded more than 500 years ago in South Asia. It has roughly 27 million followers worldwide. Observant Sikhs do not cut their hair. Male followers often cover their heads with turbans - which are considered sacred - and refrain from shaving their beards. There are roughly 500,000 Sikhs in the U.S., according to estimates. The majority worldwide live in India.
The Sikh Temple of Wisconsin started in 1997 with about 25 families who gathered in community halls in Milwaukee. Construction on the current temple in Oak Creek began in 2006, according to the temple's website.
The New York-based Sikh Coalition has reported more than 700 hate crimes in the U.S. since 9/11 and has fielded complaints in the thousands from Sikhs about workplace discrimination and racial profiling. With their turbans and long beards, Sikhs are often mistaken for Muslims or Arabs, and have inadvertently become targets of anti-Muslim bias in the United States.
The shooting also came two weeks after a gunman killed 12 people at movie theater in Colorado.
Associated Press writers Gretchen Ehlke and Scott Bauer in Milwaukee; Patrick Condon in Minneapolis; Sophia Tareen and Michelle Janaye Nealy in Chicago; Larry Neumeister in New York; Danny Robbins in Dallas; and Pauline Jelinek and Eileen Sullivan in Washington contributed to this report, along with the AP News Research Center in New York.