Last Updated 5:30 p.m. ET

(CBS/AP) OAK CREEK, Wis. - Seven people were killed and at least three people wounded in shootings at a Sikh temple outside of Milwaukee Sunday morning.

Among those killed was the gunman, who shot and wounded one police officer and was then confronted by another outside the Sikh Temple of Wisconsin in Oak Creek, near Milwaukee.

One officer was shot multiple times, and was transported to a nearby hospital, where he is in surgery. Greenfield Police Chief Brad Wentlandt said the officer, a 20-year veteran, is expected to survive.

The gunman then confronted a second officer, who returned fire, striking and killing the suspect.

Wentlandt said emergency medical personnel identified seven people dead - four inside the temple and three outside, including the suspect.

Because of the heroic efforts of the officers," said Oak Creek Police Chief John Edwards, "they stopped this from being worse than it could have been."

Edwards referred to the shooting as "a domestic terror-type incident," and said that the FBI will be taking over the criminal investigation, assisted by local police and other agencies.

Although the building has been cleared, the evidence team has still to recover weapons on the scene.

The first 911 call to police about the shooting was received at 10:35 a.m., Wendlant said. Three hours later, police were searching the temple to determine whether the gunman had an accomplice. Eyewitnesses had offered conflicting accounts; several said they believe there was more than one gunman.

A spokeswoman for Froedtert Hospital in Milwaukee, the main trauma center in the area, said doctors there are treating three victims of the shooting. Spokeswoman Carolyn Bellin said the three are all men. One is in the operating room, another is in a surgical intensive care unit, and the third is being evaluated in the emergency room.

Belliin said the hospital is prepared to receive more patients from the shooting, but does not know if more will be on the way.

Among the wounded was the temple's president, Satwant Kaleka, who was shot in the back, according to his sister-in-law, Deepinder Dhaliwal, who spoke on camera to the Milwaukee Journal-Sentinel.

In a telephone interview Sandeep Khattra told CBS News that her grandfather was shot dead, while her mother was among the temple members who hid in the temple's kitchen.

There are more than a dozen ambulances parked outside the temple, and police have corralled media and a handful of bystanders to clear out from the area near the temple.

Sukhwindar Nagr, 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. The priest also said women and children were hiding in closets in the temple, Nagr said.

The White House said President Obama was aware of the shooting and was being kept up to date by the FBI.

In a statement the Indian Embassy called the incident "tragic," and said they were in touch with the National Security Council in Washington. India's Consulate General in Chicago is also monitoring the developments, and an official is visiting the site to ascertain the situation.

Wis. Gov. Scott Walker issued a statement, saying, "Our hearts go out to the victims and their families, as we all struggle to comprehend the evil that begets this terrible violence."

Sikh rights groups have reported a rise in bias attacks since the Sept. 11, 2001, 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.

Sikhism is a monotheistic faith that was founded in South Asia more than 500 years ago. 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.

Police at this time have not identified another gunman, but Wentlandt said the situation was fluid and a search of the ground is continuing.

According to the temple's website, the temple lies on 13 acres of land. The main brick building, about 17,500 square feet in size, includes a place of worship, a library, an education area, and a playspace for children.

The temple has up to 400 members.

Oak Creek is south of Milwaukee along Lake Michigan.