Police officers outside the Emanuel AME Church after the shooting. Screenshot Nine people have been killed in a shooting in downtown Charleston, South Carolina.

The FBI and local police are investigating the shooting, which took place at a historic black church, as a hate crime, according to Charleston law-enforcement officials.

Police officers swarmed Henrietta and Calhoun streets off Marion Square in downtown Charleston about 9 p.m. local time Wednesday after the shooting was reported at 110 Calhoun St., the site of Emanuel AME Church.

Charleston police spokesman Charles Francis said the police were looking for a "white male in a gray sweatshirt/hoodie and jeans." The gunman is believed to be in his early 20s. Authorities said the suspect sat in a prayer meeting at the church for an hour before opening fire.

Surveillance video reportedly caught the man the police are seeking and his vehicle on camera:

WCSC-TV reports the shooting happened while a meeting and a Bible-study service were taking place at the church.

Six of the victims were female and three were male, authorities said at a press conference Thursday morning.

The station interviewed a photographer who was briefly detained amid the chaos immediately after the shooting. Austin Rich told WCSC-TV that the police told him he fit the description of the gunman.

Emanuel AME Church in Charleston, South Carolina. Google Maps

He was questioned and later released.

It's unclear what prompted the shooting Wednesday night, but the police have been out in full force to track down the gunman.

A bomb threat was also reported in the area, according to WBTV-TV but has since been resolved.

The Associated Press reports that helicopters were circling overhead while pastors and supporters prayed near the crime scene.

2016 presidential candidate Jeb Bush has reportedly canceled a Thursday campaign event that was scheduled in Charleston because of the shooting, ABC News reports.

Emanuel AME Church has one of the oldest and largest black congregations south of Baltimore, according to the church's website. The church dates back to the late 1700s.

The church was the target of an investigation in 1822 for its alleged involvement with a slave revolt and was burned amid the controversy. The structure was rebuilt, but services stopped when all-black churches were outlawed in 1834. The church was formally reorganized in 1865.

Here's a look at how the scene was playing out on social media:

—CNN Breaking News (@cnnbrk) June 18, 2015