OAK CREEK, Wis. (AP) — A gunman opened fire Sunday and killed six people at a Sikh temple near Milwaukee before he was killed in an exchange of gunfire with one of the first officers to respond to the chaotic scene, authorities said.

The shootings happened before 10:30 a.m., as several dozen people gathered at the Sikh Temple of Wisconsin for Sunday services. Hours of uncertainty followed as police in tactical gear and carrying assault rifles surrounded the temple with armored vehicles and ambulances, and witnesses struggled with unrealized fears that multiple gunman had taken hostages inside.

"We never thought this could happen to our community," said Devendar Nagra, 48, Mount Pleasant, whose sister escaped injury by hiding in the temple's kitchen. Other women and children barricaded themselves in closets. "We never did anything wrong to anyone."

The first official word from police was that they didn't know how many victims or suspects were involved. But after an extensive search of the temple, authorities said they did not believe there was more than one shooter.

At a news conference late Sunday afternoon, Oak Creek Police Chief John Edwards released no information about the suspect, including his identity or a possible motive. Edwards said the FBI will lead the investigation because the shootings are being treated as an act of domestic terrorism.

Jatin Der Mangat, 38, of Racine, said his uncle Satwant Singh Kaleka, the temple's president, was one of those shot, but he didn't know the extent of Kaleka's injuries. When he later learned of the deaths, Mangat said "it was like the heart just sat down."

"This shouldn't happen anywhere," he said.

Edwards said the gunman "ambushed" one of the first officers to arrive at the temple as the officer tended to a victim outside, and shot the officer multiple times. A second officer then exchanged gunfire with the suspect and fatally shot him. Police had earlier said the officer who was shot killed the suspected shooter.

Tactical units went through the building and found four people dead inside the temple and two outside, in addition to the shooter. Two others were wounded along with the police officer, Edwards said.

The three wounded were being treated at an area trauma center. Greenfield Police Chief Bradley Wentlandt, who assisted the investigation, said the police officer had surgery and is expected to survive.

Police released few details about victims, but family members talked about discussions with some of those inside.

Sukhwindar Nagra, of Racine, said he called his brother-in-law's phone and a priest at the temple answered and told him that his brother-in-law had been shot, along with three priests.

Gurpreet Kaur, 24, of Oak Creek, said her mother and a group of about 14 other women were preparing a meal in the temple kitchen when the gunman entered and started firing. Kaur said her mother felt two bullets fly by her as the group fled to the pantry. Her mother suffered what Kaur thought was shrapnel wound in her foot.

Many Sikhs in the U.S. worship on Sundays at a temple, or gurdwara, and a typical service consists of meditation and singing in a prayer room where worshippers remove their shoes and sit on the floor. Worshippers gather afterward for a meal that also is open to community members, regardless of their religious beliefs.

Kaur said she spent the afternoon serving as a translator between law enforcement and survivors at a nearby bowling alley where people had been taken from the temple.

"These are people I've grown up with," she said. "They're like aunts and uncles to me. To see our community to go through something like this in numbing."

Sixteen-year-old LeRon Bridges, of Oak Creek, works at the bowling alley and said he was in a supply closet when he heard four gunshots. He looked outside, saw police coming and went to get his boss.

"There were more and more police showing up," he said. "They all pulled out their assault rifles and ran toward the building."

Bridges said police brought people over from the temple in two armored trucks. At one point, about 50 to 60 people were at the bowling alley, including police officers questioning witnesses and paramedics treating victims' wounds, he said.

"They were just hysterical," Bridges said. "There were kids. One big load came out of the truck."

Sikhism is a monotheistic faith founded more than 500 years ago in South Asia. It has roughly 27 million followers worldwide. Observant Sikhs do not cut their hair; male followers often cover their heads with turbans — which are considered sacred — and refrain from shaving their beards. There are roughly 500,000 Sikhs in the U.S., according to estimates. The majority worldwide live in India.

The Sikh Temple of Wisconsin started in 1997 with about 25 families who gathered in community halls in Milwaukee. Construction on the current temple in Oak Creek began in 2006, according to the temple's website.

Sikh rights groups have reported a rise in bias attacks since the Sept. 11 terrorist attacks. The Washington-based Sikh Coalition has reported more than 700 incidents in the U.S. since 9/11, which advocates blame on anti-Islamic sentiment. Sikhs don't practice the same religion as Muslims, but their long beards and turbans often cause them to be mistaken for Muslims, advocates say.

Police in New York and Chicago issued statements saying that, as a precaution, they were giving Sikh temples in those cities additional attention. The Wisconsin shooting came two weeks after a gunman killed 12 people at movie theater in Colorado.

___

Associated Press writers Gretchen Ehlke in Milwaukee, Pat Condon in Minneapolis and Sophia Tareen and Michelle Janaye Nealy in Chicago contributed to this report.