(CNN)Several people were killed in a shooting at an historic African-American church in Charleston, South Carolina, a source close to the investigation told CNN.
The shooter is still at large.
The shooting took place Wednesday evening at the Emanuel African Methodist Episcopal Church, the oldest AME church in the South.
Police haven't said how many people have been shot. But the source who spoke to CNN said several bodies were in the church that were yet to be identified.
"It's really bad. It's a very bad scene," local pastor Thomas Dixon said.
"Apparently the person just entered the church and opened fire. That part has not been fully articulated on what happened yet ... they are still looking for the suspect."
Search on for suspect
Police said the suspect in the shooting is a clean-shaven white man in his 20s, with a slender build. He was wearing a gray sweatshirt, blue jeans and boots.
Soon afterward, news cameras showed officers taking a man matching that description into custody, but police said they were still looking for the shooter.
The department asked anyone with information to call 911 dispatchers
Emanuel African Methodist Episcopal Church was formed in 1816 when African-American members of Charleston's Methodist Episcopal Church formed their own congregation after a dispute over burial grounds.
Six years later, one of the church founders was implicated in a slave revolt plot. He wasn't convicted.
During the case, the church was burned to the ground. It was rebuilt in 1834.
Heavy police presence
Every Wednesday evening, the church holds a Bible study in its basement.
Corey Wessenger, who was standing across the street from the church, said the area was swarming with law enforcement.
"I just saw a group of about 40 people escorted by cops," Wessenger told CNN by phone.
Community members gathered in a prayer circle just down the street from the scene.
Patrick Wright, a reporter with WFMY News, tweeted, "We've been told not to leave our restaurant here in #Charleston for the time being. Helicopter still circling above."