CHARLESTON, United States (AFP) - US police on Thursday arrested a 21-year-old white gunman suspected of killing nine people in one of the nation's oldest black churches in Charleston - a shooting rampage being probed as a hate crime.
The carnage at the Emanuel African Methodist Episcopal Church in the southeastern US city was one of the worst attacks on a place of worship in the country in decades, and comes at a time of lingering racial tensions nationwide.
Dylann Roof - a slight man with a bowl haircut and a youthful face - was taken into custody in neighbouring North Carolina, about a four-hour drive from the scene of the shooting, Charleston Police Chief Gregory Mullen said.
"I do believe it was a hate crime," Mullen said.
A clearly frustrated President Barack Obama said the incident showed that the United States needed to look again at how violent people get their hands on guns, calling the killings "senseless."
"At some point, we as a country will have to reckon with the fact that this type of mass violence does not happen in other advanced countries," Obama said at the White House.
"It doesn't happen in other places with this kind of frequency. And it is in our power to do something about it."
Members of the church's mainly black congregation had gathered Wednesday evening for a Bible study meeting when the shooter walked into the building, sat for about an hour and then opened fire, Mullen said.
Three men and six women were killed, and several other people were wounded. Among the dead was the church's pastor Clementa Pinckney, who was also a Democratic state senator.
Side streets around the church were sealed off with yellow crime scene tape. A police officer told AFP that some of the bodies of the victims were still inside.
A support centre for relatives of the victims was set up in a nearby hotel.
"The heart and soul of South Carolina was broken," a tearful state Governor Nikki Haley said.
HATE CRIMES PROBE
Detectives were headed to Shelby, North Carolina - where Roof was apprehended during a traffic stop - to interview the suspect and gather evidence, Mullen told reporters.
The shooting comes at a time of heightened racial tensions in America, after several high-profile killings of unarmed black men at the hands of white police in recent months led to protests and a national debate on race.
A Justice Department spokesman said a hate crimes probe had been opened, with FBI agents working in tandem in with local police.
"The fact that this took place in a black church obviously also raises questions about a dark part of our history," Obama said.
A picture on Roof's Facebook page showed him wearing a black jacket with patches emblazoned with the flags of apartheid-era South African and white minority-ruled Rhodesia, now Zimbabwe.
Jim Curley, owner of AC's Bar & Grill, which is located a few blocks from the church, said locals were shocked anyone would carry out an attack in the popular tourist area.
"This is really completely out of the blue... We have no idea what the motivation is," Curley told AFP.
Darlene Green, a 56-year-old black resident of Charleston, agreed.
"South Carolina is a place of warmth. It's not normally a place where you have violence like this," Green said. "Only (the suspect) and God know what happened."
Charleston is known locally as "The Holy City," due to its large number of churches and historical mix of ethnic groups that brought a variety of people to the Atlantic coast city.
"In this great country, we hold sacred the places where people come and practice their faiths in safety and in peace," Mayor Joseph Riley said.
Dot Scott, the head of the local chapter of the National Association for the Advancement of Coloured People (NAACP), said the shooter may not have drawn attention because of the church's location.
"It sits in an area that a lot of the tourists frequent. It's not out of the ordinary that folks just walk into the sanctuary and sit and listen to what's going on," Scott told CNN.
Officials have not released details about most of the victims, or say what kind of gun was used.
According to its website, the Emanuel African Methodist Episcopal Church is the oldest such church in America's southern states.
The church was founded in 1816 and in 1822 was investigated for its involvement with a planned slave revolt, the website states.
Republican presidential candidate Jeb Bush canceled campaign events that had been planned for Thursday in Charleston. Democratic presidential candidate Hillary Clinton, who was in Charleston earlier Wednesday, tweeted condolences.
The Charleston shooting is the latest on a long list of mass shootings in the United States.
The deadliest in recent years include the April 2007 Virginia Tech shooting, when 32 were killed, and the December 2012 Sandy Hook elementary school shootings in Newtown, Connecticut, when a total of 27 people died, including 20 children.
In August 2012, six people were shot dead at a Sikh temple in Wisconsin by a neo-Nazi US military veteran.
Charleston is famous for its cobblestone streets, Southern cuisine and nearby beaches and islands. The city is also known outside the United States for its namesake 1920s dance.