A white man walked into a historic African-American church in Charleston, South Carolina, and opened fire during a Bible study class, killing nine people Wednesday evening.
The suspect was still at large early Thursday morning. And the shooting at the Emanuel African Methodist Episcopal Church, the oldest AME church in the South, is being investigated as a hate crime.
"The only reason someone would walk into a church and shoot people that were praying is hate," said Charleston Mayor Joe Riley.
Eight churchgoers died at the scene; a ninth at a hospital, police said.
Officials wouldn't say how many people were at the prayer service during the shooting. There were survivors, said Charleston Police Chief Greg Mullen, but he didn't elaborate.
Emanuel African Methodist Episcopal Church has been a presence in Charleton since 1816 when African-American members of Charleston's Methodist Episcopal Church formed their own congregation after a dispute over burial grounds.
It was burned to the ground at one point, but rebuilt.
Every Wednesday evening, the church holds a Bible study in its basement.
The shooting was "obviously the most intolerable and unbelievable act possible," the mayor said.
"People in prayer Wednesday evening. A ritual, a coming together, praying, worshiping God. An awful person come in and shoot them is inexplicable," Riley said.
Police received the first call around 9:05 p.m. Officers arrived to find several victims inside.
"It's really bad. It's a very bad scene," local pastor Thomas Dixon said.
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.
"He obviously is extremely dangerous," Chief Mullen said. "We will put all our resources, we will put all of our energy in finding this individual."
The department asked anyone with information to call 911 dispatchers.
"While we do not yet know all of the details, we do know that we'll never understand what motivates anyone to enter one of our places of worship and take the life of another," South Carolina Gov. Nikki Haley said.
Heavy police presence
"Like everybody out here, we're sick to our stomachs that this could happen in a church," Rep. Dave Mack, a friend of the church's pastor, told CNN affiliate WCSC.
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.
Republican presidential candidate Jeb Bush canceled a scheduled town hall in Charleston on Thursday "due to the tragic events unfolding in South Carolina tonight."