A man wielding a shotgun entered a church and opened fire as congregants watched a youth performance Sunday, killing one person and injuring eight others, police said.

The gunman was tackled by church members and eventually taken into police custody. None of the children were injured. A hospital spokeswoman said five of the wounded were in critical condition.

Knoxville Police Chief Sterling Owen identified the man killed as Greg McKendry, 60, a longtime church member and usher at the Tennessee Valley Unitarian Universalist Church.

"It appears Mr. McKendry was the first person he (the gunman) encountered when he walked into the sanctuary," Owen said. "It's going to be a while before all the facts are cleared up."

A church member who arrived moments after the shooting said the gunman fired three times and was tackled. Steve Drevick said he spoke to several eyewitnesses and that no one at the church recognized the gunman. He did said the gunman had more ammunition on him.

Officials wouldn't say exactly how many people helped subdue the gunman.

"It was a large group and we are thankful for them for without it, this situation could have been even worse," Mayor Bill Haslam said.

There were about 200 people at the time of the shooting watching a youth performance being put on by 25 children.

Church member Marty Murphy told The Knoxville News Sentinel that she was about 30 to 40 feet from the shooter when the rampage began.

"We heard the first shot," she said. "It sounded like a bomb went off. We thought it was part of the program at first."

She said church members dove under church pews and others ran out the sanctuary.

Murphy told the newspaper some of the children were close to the shooter when the attack began.

"One little girl had blood all over her," she said. "She was just hysterical. I don't know how that girl is going to sleep tonight."