Editor's note: An earlier version of this story ran in 2011, around the 10-year anniversary of the 9/11 terrorist attacks.
By Jose G. Santos, CNN
Fairfax Station, Virginia (CNN)– Ten years ago, Balbir Singh Sodhi was gunned down, apparently because he looked Muslim or Arab.
He was neither.
Sodhi was a Sikh. Members of the religious tradition say he was the first person to be murdered in retaliation for the 9/11 attacks.
That claim has been backed up by the Justice Department.
"The first person killed in post-9/11 violence, Balbir Singh Sodhi, was a Sikh, shot while pumping gas at his gas station in Arizona four days after 9/11," said Assistant Attorney General Thomas E. Perez in congressional testimony earlier this year.
For American Sikhs, Sunday's deadly attack on worshippers at a Sikh temple outside Milwaukee dredged up memories of other recent attacks against their community.
At least seven people, including a gunman shot by a police officer, were killed in Sunday's attack.
In the case of the post 9/11 attack on in Arizona, a 45-year-old aircraft mechanic named Frank Roque gunned down a bearded, turban-wearing Indian immigrant outside a Mesa gas station. Roque drove up to the station, fired a handgun at Balbir Singh Sodhi - who owned the station - five times, then fled.
Roque would go on to shoot at a Lebanese-American gas station clerk and fire into the home of an Afghan-American family later that same day.
In 2003, Roque was sentenced to death for Sodhi's murder. On appeal, his sentence was reduced to life in prison.
Blending in, standing out
Ten years after the September 11 attacks, which provoked a wave of organizing among Sikhs worried about being mistakenly targeted in retaliatory attacks, adherents of the religion remain both visible and enigmatic.
"Most of the challenges we face can be traced to people not knowing who we are," said Jasjit Singh, assistant executive director at the Sikh American Legal Defense and Education Fund, in an interview last year. "I don't feel there is a specifically anti-Sikh bias, because people don't know what Sikhs are."
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Singh's group estimates that there are about 500,000 Sikhs in the United States, nearly all of Indian origin.
Sikh women are less identifiable than men, identifiable by their beards and turbans. Many American Sikh women dress like other Westerners or wear the salwar kameez, a traditional north Indian garment of a long shirt and loose-fitting pants.
A woman prays during a Sikh service.
Sikhism emerged more than 500 years ago in Punjab, in what is now India.
Adherents of the monotheistic faith believe in "devotion, remembrance of God at all times, truthful living, equality between all human beings, social justice, while emphatically denouncing superstitions and blind rituals," according to the website of the Sikh Coalition, a U.S.-based group.
"The ultimate goal in Sikhism is to merge into the divine love we know is God," said Navdeep Singh, a policy adviser to the Sikh American Legal Defense and Education Fund, in an interview last year.
"We believe in the cycle of reincarnation," he said. "That you will be judged by your deeds, and come back, and each time you come back you move one step closer to the divine."
There are 25 million Sikhs around the world, according to the Sikh Coalition, which was formed after the September 11 attacks.
Congregants meet inside a Sikh temple in Virginia.
Inside the temple
A Sikh temple is called a gurdwara, which means door to the guru, or teacher.
Gurdwara refers to both a place and a practice, encompassing temple, teachings and ceremony.
Gurdwaras around the world variously incorporate clinics, schools, guest quarters and community centers, which Sikhs say is a sign of the religion's values of service and equality.
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"Sikhism was founded in an area and in a time in which inequality was rampant," said Navdeep Singh. "If you were a woman, you were less than a man. If you were poor you were less than a rich person. Based on what caste you were, that defined your entire life. Sikhism was a rejection of those ideas."
At the gurdwara known as the Sikh Foundation of Virginia, the muffled trills of a harmonium blended with birdsong on a recent Sunday morning.
The golden dome of the Sikh Foundation of Virginia.
The temple's golden dome shimmers among the rustling dark green woods like a crown atop a velvet cushion.
As worshipers enter, shoeless and with heads covered, they approach the Guru Granth Sahib, a book elaborately enthroned beneath a canopy at the head of the building's main hall.
Obeisance is made, and a gift, usually of money, is placed on the dais. Music, song, prayer, readings from the Guru Granth Sahib and sermons comprise most of the ceremony. Everyone sits on the floor, men on one side, women on the other, children wherever suits them.
Congregants meet for prayer and study in Virginia.
"The beginning of our Guru Granth Sahib, and Sikh philosophy is really encapsulated in the first phrase: 'Ik Onkar,' which means 'there is one God,' " said Navdeep Singh.
More than a book of scripture, the Guru Granth Sahib is considered to be a living teacher, or guru.
After the service congregants share a communal meal.
After the worship service, called Diwan, comes Langar, a simple meal eaten while sitting on the floor, which Sikhs say reinforces the ethic of egalitarianism.
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"Langar is based on this idea of equality, and making sure that no one goes away hungry," said Navdeep Singh. "Because as Sikhs, we're kind of like Italians. We view everyone as one family. And if you're part of that family, you can't go away hungry. You have to have a meal together."
if hindus say that sikhs are bad, muslims are bad and christians are bad and oly hindus are good, it is hard to believe bcoz they have murdered their own citizen 4 times, skhs in 1984, muslims in 1992 and 2002, christians in 2008 just for the name of their religion.
The CNN Belief Blog covers the faith angles of the day's biggest stories, from breaking news to politics to entertainment, fostering a global conversation about the role of religion and belief in readers' lives. It's edited by CNN's Daniel Burke with contributions from Eric Marrapodi and CNN's worldwide news gathering team.