Sister of Charleston shooter Dylann Roof arrested after menacing social media post

The younger sister of convicted mass murderer Dylann Roof — who gunned down nine parishioners at a Charleston church in 2015 — was arrested Wednesday on drug and weapons charges after she posted a disturbing message on social media.

Morgan Roof, 18, a student at AC Flora High School in Columbia, was charged with one count of marijuana possession and two counts of carrying a weapon on school grounds, the Richland County Sheriff's Department said, describing the weapons as a knife and pepper spray, according to The State newspaper.

WACH-TV in Columbia reports:

"No students were harmed and [Morgan Roof] has been transported to the Alvin S. Glenn Detention Center.

She [appeared] in bond court Wednesday night where her bond was set at $5,000 and was charged with carrying weapons on school property. She was also ordered not to [return] to the incident location."

Roof's arrest came after she reportedly posted a message to Snapchat saying that she hoped students participating in Wednesday's walkout of classes to protest gun violence would "get shot" and suggested that only "black people" would be participating in the nationwide protests.

"Your walking out of the allowed time of 17min, they are letting you do this, nothing is gonna change what tf you think it's gonna do? I hope it's a trap and y'all get shot we know it's fixing to be nothing but black people walkin out anyway," she posted.

Sheriff Leon Lott said after learning of the post, the school's staff called the School Resources Officer and that Roof was promptly arrested.

Susan Childs, the principal of AC Flora, said in a statement to parents and students: "As many of you know, today was set as a time for a student walkout. Our student leaders had asked to be allowed to spend seventeen minutes to remember each of the victims of the Parkland, Florida school shooting."

"[A] student used social media to post a hateful message. The posting was not a threat, but was extremely inappropriate. That student was dealt with in a swift and severe manner as the posting caused quite a disruption," Childs said.

South Carolina Gov. Henry McMaster said in a statement that a "[p]otential tragedy was avoided" at the school.

"We owe a debt of gratitude to all involved who acted so quickly and decisively," McMaster said.

Dylann Roof, a self-avowed white supremacist, killed nine African-American parishioners during a bible study at Charleston's Mother Emanuel African Methodist Episcopal Church in June 2015.

In January 2017, he was sentenced to death by lethal injection. Roof pleaded guilty to state murder charges and was found guilty by a jury in Charleston on 33 counts of federal hate crimes. He is currently awaiting execution at the United States Penitentiary in Terre Haute, Ind.