Sister of South Carolina mass shooter arrested on weapons charges

The sister of avowed white supremacist Dylann Roof, who was sentenced to die for the 2015 massacre at a historic South Carolina black church, was arrested on Wednesday for carrying weapons at a high school, media said.

Morgan Roof, 18, was carrying a knife and pepper spray, as well as marijuana, at a school in Columbia, S.C., the Post and Courier and other media reported.

The arrest came on the morning of a protest walkout by thousands of students nationwide to demand gun law reform in the wake of a Florida mass shooting that killed 14 students and 3 teachers a month ago.

Morgan Roof also alarmed authorities with a racially charged Snapchat post against the walkout, saying in part, "I hope it's a trap and y'all get shot," the newspaper and other media said.

In response, South Carolina Gov. Henry McMaster called for more security at schools.

"For months, I have called on the general assembly to join me in placing a trained, certified police officer in every school," he said in a statement.

She was held in custody late on Wednesday on a bond of $5,000 and ordered not to return to the campus, media said.