Whatever caused Wade Michael Page to massacre worshipers at a Wisconsin Sikh temple on Sunday may never be known. But for at least a decade, he had been steeped in a neo-Nazi "hate music" scene.
Law enforcement agencies and civil rights organizations that monitor hate groups have been paying attention to these music groups and their followers since the genre began to emerge in the United States in the early 1980s.
The Anti-Defamation League estimates that there are 100 to 150 active or semi-active bands that perform and release such music in the United States.
Aiming to energize followers and intimidate others, many of these bands boast names that favor shock over subtlety — Jew Slaughter, Angry Aryans, Ethnic Cleansing. Page, a guitar player and singer, was once a member of 13 Knots, a name that refers to the number of knots in a noose.
"The main theme of these groups is to create anger and direct it toward perceived enemies: Jews, blacks, other minorities," said Mark Pitcavage, director of investigative research at ADL, who has been tracking hate music since the early 1990s. The music, he added, is also intended to "create a group sense, praising or glorifying skinheads or white supremacists like themselves."
The music these bands play takes various styles but the most prevalent are racist variations of some of rock's most aggressive forms, such as Oi!, an early punk style that emerged in Great Britain in the 1970s; hard-core punk; and death metal, a particularly bludgeoning style of heavy metal punctuated by storming guitars and guttural howls.
Concerts and festivals are held periodically across the country, the most well-known of which is Hammerfest, a concert put on by the Hammerskins, a white supremacist skinhead organization that is actively involved with white power music.
End Apathy, a band that Page founded, had released songs on a Maryland-based record label, Label 56, that also distributed recordings by dozens of white power bands from the United States and Europe.
On its website Monday, Label 56 distanced itself from the Wisconsin shooting and removed all End Apathy content. One of the label's owners, Clemie Richard Haught Jr., did not respond to multiple requests for comment. A statement on the label's website said: "Please do not take what Wade did as honorable or respectable and please do not think we are all like that."
Page, 40, was shot to death by a Wisconsin police officer after he killed six Sikh worshipers at a temple in Oak Creek, Wis., on Sunday. He was discharged from the Army in 1998 because he had been found drunk during military exercises, according to law enforcement authorities. He was convicted of driving under the influence a year later in Colorado. And a trucking company confirmed Tuesday that it fired Page two years ago after he was pulled over in North Carolina for driving while impaired.
Investigators are working to determine Page's motive for the shooting, which also left a police officer and two others wounded.
Officials said Monday that they think Page acted alone when he opened fire at the Sikh Temple of Wisconsin in Oak Creek, a Milwaukee suburb.
There is no evidence that Page harbored specific resentment toward Sikhs. Watchdog groups and Sikhs say it is likely that Page confused the religion with Islam, because Sikh men wear beards and turbans.