CHARLESTON, S.C. (CBSNewYork/AP) — The man accused of killing nine people at a historic black church in Charleston, South Carolina may be linked to a racist manifesto posted online.

The alleged manifesto, a text file accompanied by a zip drive with photos, was uploaded to a website called “lastrhodesian,” a domain which appears to have been registered early this year, by someone using the name Dylann Storm Roof, CBS News reported.

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A law enforcement source told CBS News that investigators were aware of the online manifesto and were looking into its legitimacy and its contents.

Roof, 21, allegedly shot and killed nine people inside Emanuel African Methodist Episcopal Church during a bible study Wednesday night.

A federal law enforcement source said Roof planned the shooting for months and picked the historic site because he wanted to “start a race war.”

The text document includes writings about killing black people in Charleston because it’s one of the most historic cities in the state with no skinheads or real KKK groups:

“I have no choice. I am not in the position to, alone, go into the ghetto and fight. 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.”

The purported manifesto states that Roof’s attitudes toward racism shifted during the Trayvon Martin case, and that he was “not raised in a racist home or environment,” CBS News reported.

The site also includes pictures of Roof posing with weapons and wax figures of slaves.

The 21-year-old is charged with nine counts of murder and one of possession of a weapon during the commission of a violent crime.

State Sen. Clementa Pinckney, 41, a pastor at the church; Cynthia Hurd, 54; Tywanza Sanders, 26; Myra Thompson, 59; Ethel Lance, 70; Susie Jackson, 87; and the reverends DePayne Middleton Doctor, 49; Sharonda Singleton, 45; and Daniel Simmons Sr., 74 were killed Wednesday as they gathered for bible study.

On Saturday, a parishioner with the Emanuel African Methodist Episcopal Church said it will be open for Sunday morning services.

Meanwhile, in New York City, Mayor Bill de Blasio and other local leaders led a rally and march in support of the shooting victims.

Mayor Bill de Blasio marches following #IamAME rally at Greater Allen A.M.E. Cathedral of New York in Queens (Credit: Roger Stern/1010 WINS)

Mayor Bill de Blasio marches following #IamAME rally at Greater Allen A.M.E. Cathedral of New York in Queens (Credit: Roger Stern/1010 WINS)

Following the rally, dubbed #IamAME, at Greater Allen African Methodist Episcopal Cathedral of New York in Jamaica, de blasio said he thinks it’s time to have a blunt conversation about the availability of guns and mental health problems related to massacres.

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