BELLS will be rung by churches of all denominations in Charleston, South Carolina, at 10 a.m. local time on Sunday (3 p.m. BST) as an act of unity after the shooting in the city's Emanuel African Methodist Episcopal Church on Wednesday, in which nine people were killed.

"Charleston is often referred to as the 'holy city'; a place where church steeples - not skyscrapers - dot the skyline," the city's visitors' bureau said in a statement. "This Sunday, our bells will ring loudly and proudly to proclaim our community's unity.

"More than three centuries ago, Charleston was founded on the principle of religious tolerance. As a result, we live, work, and raise our families in a historically strong and welcoming community. We now call upon our collective strength to renew Charleston's unity and compassion."

The African Methodist Episcopal Church is the oldest Black-led denomination in the United States. It was founded by a freed slave, Richard Allen, in 1816, and will mark its bicentenary next year.

The man suspected of carrying out the shooting, Dylann Roof, aged 21, reportedly sat through a Bible-study group at the church for an hour before opening fire, killing nine people including a janitor, a sports coach, and the church's pastor and a South Carolina State Senator, the Revd Clementa Pinckney.

Joey Meek, a friend of the suspect, told ABC News that Roof thought that black people were "bringing down" white people, and wanted a return to segregation. Media reports describe him as a white supremacist with a history of drug abuse and racism.

Roof was arrested by traffic police in Shelby, North Carolina, on Thursday, and was flown back to Charleston. Handcuffed, and chained at the ankles, Roof wore a bulletproof vest over striped clothes as he was transported by police.

On Friday afternoon we was charged with nine counts of murder, and a tenth charge of illegal possession of a firearm. Sources close to the investigation have been quoted by US media as saying that Roof has confessed to the killings. The Governor of South Carolina, Nikki Haley, has called for the death penalty if Roof is convicted.

Chris Singleton, a teenager, lost his mother, Sharonda, a school sports coach, in the shooting. Speaking after a memorial service in the school's sports hall, he told BBC News that the family had forgiven the killer.

"We already forgive him for what he's done, and there's nothing but love from our side of the family," he said.

The Bishop of the Episcopal diocese of South Carolina, the Rt Revd Charles G. vonRosenberg, said that the "unimaginable tragedy" called for "prayer, response, and self-examination".

He said: "In our prayers, may we remember the victims, their families, the community of faith that is Emanuel, the wider communities of faith in the AME Church, and our society, so prone to violence.

"As paths of response, may we seek and develop avenues of racial conversation and reconciliation; may we refuse to accept things as they are in our world; and may we strive for the vision of peace offered by Jesus himself.

"In terms of self-examination, may we not neglect our own complicity in an environment of polarisation and suspicion, and may we respond with sincere and profound confession to God, who loves us all."

Other church leaders have also commented on the shooting. "Arresting the shooter is the job of law enforcement. Arresting hate is the work we are all called to do as disciples of Jesus Christ," the Moderator of the General Assembly of the Presbyterian Church in the US, Heath Rada, said in a joint statement with other denominational officials.

"May God never give up on us, as we face our own racism and its tragic impact on congregations, their communities, and our very souls."

The Roman Catholic Bishop of Charleston, the Most Revd Robert E. Guglielmone, said that he was "deeply saddened" by the incident.

"The inside of any church is a sanctuary," he said. "When a person enters, he or she has the right to worship, pray, and learn in a safe and secure environment. For anyone to murder nine individuals is upsetting; but to kill them inside of a church during a Bible study class is devastating to any faith community.

"On behalf of the Catholic faithful in South Carolina, I offer my deepest sympathies to the families of the victims, and to the members of Emanuel AME Church. I pray that everyone affected by this horror will feel the comforting presence of our Lord surrounding them during this difficult time."