Authorities investigating the fatal shootings at a black church in the United States are looking into a racist manifesto, apparently written by the 21-year-old suspect.
The FBI said on Saturday that it was reviewing the manifesto purportedly written by Dylann Roof, who is currently in police custody, Associated Press reported.
A federal law enforcement official close to the investigation said the FBI is aware of the website and is reviewing it. The official spoke on condition of anonymity because he was not authorised to speak publicly on the case.
The website also hosts a series of photographs that appear to show the suspect, a white man from Lexington in South Carolina.
| Confederate flag: A symbol of racially segregated past
Demonstrations are being held against the flying of the Confederate flag in South Carolina's capital, Columbia.
The flag was used by those who fought to secede from the US in its Civil War over slavery and is seen by many as a symbol of racism and segregation.
Activists are calling for the removal of the controversial flag from the grounds of the state house because of what some people see as its racist associations.
US President Barack Obama has said that he believes the flag belongs in a museum.
The authenticity of the website, which surfaced on Saturday, or who created it, could not be immediately confirmed. But Al Jazeera's Gabriel Elizondo, who is reporting from the city of Charleston, has confirmed that it was registered by Roof.
Al Jazeera has also spoken to Roof's father, but he would not confirm that his son created the site.
In the website, the author provides a cryptic "explanation", for action, saying, "I have no choice ... I chose Charleston because it is most historic city in my state, and at one time had the highest ratio of blacks to whites in the country.
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It also shows a photo of the suspect carrying a gun and the Confederate flag.
The website surfaced as mourners arrived in the city of Charleston from around the US on Saturday, to pay their respects to the nine African American victims.
|Activists are calling for the removal of the controversial flag from the grounds of the state house [EPA]
Church leaders have confirmed that it will reopen on Sunday for the first service since the shooting.
At the memorial site in front of the Emanuel African Methodist Church, the oldest African American congregation in the southern US, flowers were laid two metres deep in places.
"Raw emotions pouring out into the streets here in Charleston and all over South Carolina as people continue to mourn over the terrible massacre," Al Jazeera's Elizondo said.
Crowds gathered at the historic church on Saturday, while placards and signs offered words of solace and prayer but also frustration at another act of gun violence.
A black T-shirt hung on the church gate had white lettering that read: "Do you believe us now? Change must come."
Monte Talmadge, a 63-year-old US navy veteran, drove nearly 480km overnight from Raleigh, North Carolina, and sat in a camping chair across the street from the church.
The bloodshed in Charleston is the latest in a series of fatal mass shootings in the US.
The violence has renewed a national debate on tighter controls on gun possession, as well as racial discrimination against African Americans in the country.
Roof was arrested on Thursday and charged with nine counts of murder and a weapons charge for the fatal shooting at the church.
|People gather at a rally calling for the Confederate flag to be taken down, at the South Carolina State House Building in Columbia, South Carolina [EPA]