As more details are unearthed about Wade Michael Page, the alleged murderer of six Sikhs at a temple in Oak Creek, Wis., it's clear he "was nothing if not a relentless promoter of hate and the style of music he loved," says Nick R. Martin at Talking Points Memo. That music would be the white-power hard-core rock he played in several bands, one of many clues to his participation in the white-supremacist movement. Page, shot dead by police at the scene of the crime, can't answer any questions, but here's a look at what we know about his ideology, connections to white-power groups, and troubling musical career:

How do we know Page was a white supremacist?
There are a number of red flags in the photographs of Page that are trickling out, most notably shots of him playing guitar with his band End Apathy, says Scott Eric Kaufman at Lawyers, Guns & Money. In those photos you'll find such "subtle clues" as a Nazi flag backdrop, a Confederate flag pattern on his guitar strap, and the tattoos covering his arms and back. The Southern Poverty Law Center (SPLC) had been tracking him as a white-power extremist since 2000, as had the Anti-Defamation League (ADL) since 2010. "Whether his white-supremacist beliefs influenced his decision to murder peaceful Sikhs, that may well be a matter for debate," Kaufman adds, but there's little doubt "he was a white supremacist." 

What do his tattoos tell us?
The local police say that Page's tattoos were their first clue that the shooting spree was an act of domestic terrorism, says Adam Weinstein at Mother Jones. And it's easy to see why: "Much of his body reads like a poster text for white nationalism." The most obvious tells are the tattoo of a Nazi Death's Head, the insignia for one of the divisions of the World War II Nazi army, and, on his left shoulder, a large Celtic cross intertwined with the number 14 — a reference to "the 14 words," a credo of white supremacist David Lane: "We must secure the existence of our people and a future for white children." His right shoulder reportedly bears the symbol of the white-power group the Hammerskins (a black, yellow, and red cogwheel with the numbers 838).

Who are the Hammerskins?
The Hammerskins, started in Texas in the 1980s, are now "the big dogs of the white-supremacist movement," says Mark Pitcavage, the ADL's director of investigative research. The ADL says the Hammerskins is "a long-­stand­ing hard­-core racist skin­head group with a his­tory of violence and hate crimes." The group gets its name from the Pink Floyd movie The Wall, where the character Pink delves into Nazi-like fascism and adopts the symbol of two crossed hammers. The umbrella group Hammerskin Nation embraces about 20 local and regional chapters in the U.S., and 10 more in Canada, Europe, Australia, and New Zealand. Stateside, its goal is "American monoculture," says Robert Crook at Open Salon: "A culture of white, patriarchal, usually theocratic so-called 'Christians'" who've rid the country of anyone "whose race or beliefs or language or customs or sexual orientation or gender identification" doesn't match up. In late 2011, after an apprenticeship period, Page became a "fully patched" member of the Hammerskins.

What other groups did Page belong to?
In an April 2010 interview with the webzine Uprise Direct, Page said he became involved in the skinhead music scene in 2000, when he sold all his belongings and took a motorcycle trip across the country, staying with friends and attending white-supremacist rock shows and festivals. Landing in Southern California, Page played bass in a number of white-power bands — Youngland, Celtic Warrior, Radikahl, Max Resist, Intimidation One, Aggressive Force, Blue Eyed Devils, and more recently, Definite Hate — before starting his own, End Apathy, in 2005. 

What's the deal with white-power rock?
It may seem like a faddish throwback to the racist skinhead punk rock in Europe in the 1970s and '80s, but white-power music is a mainstay of the Hammerskins, and a "fairly important part of the white-supremacist subculture" in the U.S. today, says the ADL's Pitcavage. There's a lot of secrecy involved: Band members commonly use only their first names, and concert venues are often kept secret. Page's record distributor, Label 56, is part of the white-power ecosystem, but removed all End Apathy music and merchandise from its website on Monday. "We do not wish to profit from this tragedy financially or with publicity," the label said in a statement. "Please do not take what Wade did as honorable or respectable, and please do not think we are all like that."

Why didn't Page raise red flags with law enforcement?
Even though the SPLC and ADL had been tracking Page for years, the FBI and Wisconsin police said Monday he "was never on their radar," says Talking Point Memo's Martin. That's partly because he had recently moved to the state from North Carolina, but the truth is "there are tens of thousands of people like this," the SPLC's Mark Pokok tells The Daily Beast. He didn't have a violent criminal record, and, in cases of lone-wolf attacks, which the Sikh temple shooting appears to be, "it is almost impossible to predict who is going to go out and commit a murder." If race was indeed the motive, Page was probably frustrated with the so-called "meet, eat, and retreat" leadership of the white-supremacy movement, Potok adds. White-supremacist participation and arrests have shot up in the past three years, but sometimes "someone gets sick of the group not doing anything, and wakes up one morning and decides to go out and start killing people."

Sources: Anti-Defamation League (2), Daily Beast, Lawyers Guns & Money, Mother Jones, NBC News, New Yorker, Open Salon, Southern Poverty Law Center, Talking Points Memo, Washington Monthly