Tonight, an fbi investigation is under way into what provoked a shooting spree this weekend and whether it could have been prevented. Just two weeks after the shooting in aurora, colorado, a gunman... See More
Tonight, an fbi investigation is under way into what provoked a shooting spree this weekend and whether it could have been prevented. Just two weeks after the shooting in aurora, colorado, a gunman opened fire in a sikh temple in wisconsin killing six. Today, president obama called for americans to do some soul searching as new details emerged linking the suspect to the neo-nazi movement. Abc's brian ross has the latest on the tragedy at the temple. Reporter: It was a senseless slaughter. And last I heard, a balding man with glasses may have gone inside with a gun and there were shots fired. Reporter: Six people killed at a sikh house of worship. My dad was shot on the ground. Reporter: Amardeep kalika's father. Killed inside the temple. And they're saying that the people are still in there. Ambulance up, subject down. Reporter: Among the first on the scene, 51-year-old brian murphree. He shot at close range. Reporter: The shooter, an army veteran, because of longtime ties to the neo-nazi world wade michael page. The shooting should help focus attention on the shadowy world in which page became there. Reporter: Officers came in seeking to help lieutenant murphy. He'd been shot nine times. One of them very serious in the neck area and whaeved them off to tell them go into the temple to assist those in there. Reporter: Today with oak creek and others around the country in mourning, three people were hospitalized, including the police lieutenant. And members of the sikh community are trying to understand why they, a rather peaceful organization have been targeted by what police call a domestic act of terror. It looks to me that this time, I'm very, very scared of this thing. I never expected this incident, especially in america. Reporter: Civil rights groups say the answer could come from the subterranean world of white power and it's neo-nazi rock bands with their anthems. Southern poverty law group said it has tracked the suspect, wade michael page ten years as he's moved through the skinhead circle. He first appeared on the white supremy in year 2000. Reporter: Page's group called end apathy, its songs including self-destruct and submission have been well documented by the anti-defamation league. ♪ Adapt to the trying times or pay with your life ♪ the basic idea that these pe have that they are defenders of the white race which is subjected to the genocide by the miserable multiculturalists and so on. Reporter: Page enlisted in the army at the age of 21 at ft. Bragg, north carolina. The army said page was discharged in 1998, after being demoted from sergeant to specialist and deemed ineligible for re-enlistment. His stepmother, laura page, told abc news tonight that the arm changed the young man she knew growing up in texas. I don't know if the military was good for him. I don't know. I wish I had some answers. And we're not going to have those answers now because he's dead. have moved to the milwaukee area this year. The neighbors say he was not very friendly. On a scale of 1 to 10, about a 1.5. Reporter: Federal officials say page bought the pistol used in the rampage just eight days earlier. If we did everything right, there's nothing I can do to change it. Reporter: The changes came after he lost his job. Today, they lowered the flag in respect. This isn't the kind of thing that gets cooked up in back rooms with large groups of white men. What we're seeing, apparently, is lone wolf terrorism. Reporter: Some of the pr prominent websites label page was cowardly.
This transcript has been automatically generated and may not be 100% accurate.