As the young white man charged with murdering nine people inside an historic black church in South Carolina stood blankly silent during a court hearing on Friday, relatives of slain worshippers addressed him one by one, offering tearful words of grief and forgiveness.

Dylann Roof, 21, who authorities say spent an hour in Bible study with parishioners at the nearly 200-year-old Emanuel African Methodist Church before opening fire on them, stood quietly, stoically, as he appeared via video feed for an initial bond hearing before a magistrate judge.

Dressed in a black-and-white prison uniform and flanked by two guards in body armor, Roof showed no reaction as the judge ordered him held without bail. He was formally charged with nine counts of murder and a weapons offense.

"May God have mercy on your soul," said Felicia Sanders, whose 26-year-old son, Tywanza Sanders, was the youngest person to die in Wednesday's rampage. "You have killed some of the most beautiful people that I know. Every fiber in my body hurts."

Roof looked down occasionally and showed no emotion as Sanders and four other family members of the gunshot victims spoke of how he had been welcomed into to the church by the nine people he has been charged with slaying on Wednesday night.

The attack at the church nicknamed "Mother Emanuel" for its key role in African-American history followed a wave of protests across the United States in recent months over police killings and excessive force against unarmed black men, focusing attention on race relations and bias in the criminal justice system.

The bloodshed in Charleston, where residents packed an arena for a prayer vigil late Friday, marked the latest in a series of fatal US mass shootings. The violence has renewed a national debate between advocates of tighter controls on gun possession and supporters of unfettered access to firearms they assert is constitutionally protected under the Second Amendment.

"The elephant in the room is guns. South Carolina and the country have gone gun-crazy," said state Representative Wendell Gilliard, a Democrat who represents Charleston. "How many times do we need to come together? How many times do we need to unite?"

The US Justice Department is investigating the attack as both a hate crime and potential act of terrorism, spokeswoman Emily Pierce said on Friday.

'NO ROOM FOR HATING'

The family members filed into the courthouse in twos and threes before Roof's appearance, appearing composed as they stared at the defendant on the video monitor, who was arrested without incident on Thursday in North Carolina after 14 hours at large.

In addition to Sanders, the massacre's victims included Democratic state Senator Clementa Pinckney, 41; DePayne Middleton Doctor, 49; Sharonda Coleman Singleton, 45; Cynthia Hurd, 54; Susie Jackson, 87; Ethel Lance, 70; Myra Thompson 59, and Daniel Simmons, 74.

Roof could be sentenced to death if he is convicted, and South Carolina Governor Nikki Haley, a Republican, urged prosecutors to seek capital punishment.

Still, family members offered words of mercy during the brief court appearance.

"I acknowledge that I am very angry," said Bethane Middleton Brown, who said her slain sister, Middleton Doctor, would have urged love.

"She taught me that we are the family that love built," Middleton Brown said. "We have no room for hating, so we have to forgive."

The defendant's relatives, in their first public comment since the shooting, issued a statement through Roof's lawyer offering their "deepest sympathies and condolences" to the victims' families.

"Words cannot express our shock, grief and disbelief as to what happened that night. We are devastated and saddened by what occurred," the statement said.

'WHERE DOES THIS HATE COME FROM?'

From President Barack Obama, who has said the attack stirred memories of "a dark past," to residents on the streets of Charleston, Americans have expressed outrage at Wednesday night's bloodshed.

"This was not merely a mass shooting, not merely a matter of gun violence, this was a racial hate crime and must be confronted as such," said Cornell William Brooks, president of the NAACP. The National Association for the Advancement of Colored People was founded in 1909 to confront lynchings in the United States.

Brooks expressed anger that the South Carolina capitol continued to fly the Confederate battle flag, a symbol of the pro-slavery South during the US Civil War, and called for it to be removed.

After the shooting, Roof made a "racially inflammatory" statement to one of the three people who survived the attack, according to court papers filed on Friday, but the documents did not specify the comment.

On Friday night, mourners filled an indoor arena on the campus of the College of Charleston for a memorial vigil for the shooting victims. The racially mixed crowd included a large contingent of Charleston's white residents turning out in support.

Earlier in the day, passersby continued to flock to the AME church that remained a crime scene, many struggling to understand what motivated the attack.

The AME church was founded in the early 19th century by black worshippers who were limited in how they could practice their faith at white-dominated churches. The church was rebuilt after being burned down in the late 1820s when one of its founders drafted plans for a slave revolt.

"I grew up when racism was just a way of life," said Mary Meynardie, 90, who is white, as she stopped by the police tape that still surrounded the church. "I wouldn't have been surprised if it was somebody 60, 70 years old who had that much hate, but where does this hate come from?" – Reuters