In Sunday's attack
The gunman, identified as Wade Michael Page, shot dead six people and seriously wounded three, including a police officer, at the Sikh Temple of Wisconsin on Sunday as worshippers prepared for religious services. Police shot dead the gunman.
Although the identity of the tall, bald, white suspect in his 40s was not officially released, Fox News said Page (40) was a former soldier. Page at one time was stationed at Fort Bragg, North Carolina, Fox said, citing unnamed sources.
CNN said Page legally owned the gun that was used in the shooting.
A law enforcement official who asked not to be identified said the "name that is out there is accurate".
Authorities said they were treating the attack as an act of domestic terrorism.
Background checks
Wade had been a member of the racist skinhead band End Apathy, based in Fayetteville, North Carolina, in 2010, said Heidi Beirich, director of the intelligence project at the Southern Poverty Law Centre in Montgomery, Alabama.
Wade also tried to buy goods from the National Alliance, a neo-Nazi group, in 2000, she said.
"That's all we know about Wade. We are still digging through our files," she said.
A US official who asked not to be identified confirmed that Wade had been in the military and said it was before the September 11 2001, attacks on the US.
Police were searching an apartment at a duplex in the Cudahy neighbourhood near Milwaukee, presumed to be the residence of the gunman. Generators and floodlights were set up along the street and a bomb squad was on the scene.
Military background
The names of the victims were not made public pending notification of relatives, although members said the president of the congregation and a priest were among the victims.
Oak Creek Police Chief John Richards told CNN the suspect had a military background but gave no more details.
The suspect "lived in a community neighbouring ours, we're doing a 24-hour back check, just to get any idea what he was up to, what he was doing," Edwards said.
"Right now there is no indication that there were any red flags."
The wounded police officer had been shot eight or nine times in the face and extremities at close range with a handgun. None of the wounds were life-threatening, Edwards said.
Place of worship
"I am deeply shocked and saddened to learn of the shooting incident that has resulted in the loss of precious lives," said Singh, himself a Sikh.
"That this senseless act of violence should be targeted at a place of religious worship is particularly painful," Singh told reporters in New Delhi.
"I hope the American authorities would investigate who is behind this dastardly attack on innocent devotees and that they will ensure that such ghastly events do not take place," Singh said.
By religious tradition, Sikh Indians wear turbans to cover their uncut hair and sport long beards.
In the US, they have often been confused with Muslims and targeted by anti-Islam activists, particularly after the September 11 2001 attacks.
'Mistaken identity'
Leading Sikh politicians in India said the temple shooting in Wisconsin may have followed a similar pattern.
"I think it is a case of mistaken identity. Sikhs are often mistaken to be from the Middle East," Manpreet Singh Badal, founder-president of the People's Party of Punjab, said.
"This is an opportunity, although a very sad one, to raise awareness among Americans about the Sikh culture and identity," he said.
At Sikhdom's holiest shrine, the Golden Temple in the northern Indian city of Amritsar, the atmosphere was tense and sombre as shocked devotees went to offer their prayers, amid the daily influx of tourists.
"This attack on Sikhs in the US is shameful. People come to the gurudwara [temple] to find peace. It is a holy place," said Kulwinder Singh (50).
"Sitting in India we are helpless," said Nita Singh (45). "The US government must take steps to see such incidents never occur in the future."
Comprehensive look
Separately, Indian Foreign Minister SM Krishna said he "condemned this incident and every right-thinking person has to condemn this".
He told reporters in New Delhi that India would "like to assure the Sikh community the government of India would do everything within its powers to ensure their [US] places of worship are going to be protected".
Asked whether the shooting was a result of a "gun culture in the United States," Krishna replied New Delhi was "certainly not going to interfere in the internal affairs of United States".
At the same time, he added, Americans "will have to certainly take a comprehensive look at the this kind of [gun culture] tendency, which certainly is not going to bring credit to the United States".
In Indian Kashmir, which has a large Sikh community, protesters blocked a national highway and brandished banners calling for stronger US gun laws.
In Delhi, several dozen Sikhs demonstrated outside the US embassy and chanted slogans denouncing "hate crimes".
Educating people
"Sikhs contribute a lot to America, they are an important part of America," said Manjit Singh, president of a Delhi-based Sikh party.
"This is a racially motivated case and the [US] government needs to educate people about different communities so it doesn't happen again."
US ambassador Nancy Powell visited New Delhi's largest Sikh temple to show solidarity with the grieving community over what she described as "this ghastly act of violence".
"We hope that families find comfort in the fact that so many around the world share their grief," she told reporters.
In Amritsar, Giani Gurbachan Singh, head priest at the Akal Takht, Sikhdom's highest seat of religious and temporal authority, urged all Sikhs in the US to "remain vigilant".
"This is a security lapse on the part of US government wherein Sikhs have become the victims of violence," Singh said, adding that a "chain of prayers" would be held in Sikh temples across India, including the Golden Temple. – Sapa-AFP