FBI arrests South Carolina man they say was plotting Dylann Roof-style mass attack

COLUMBIA, S.C. — Authorities say a 29-year-old white supremacist and convicted felon bought a gun from an undercover FBI agent in South Carolina that he said he wanted to use in "the spirit of Dylann Roof."

The FBI arrested Benjamin McDowell shortly after he bought the gun Wednesday for $109 in Myrtle Beach. McDowell is charged with being a felon in possession of a firearm.

Benjamin McDowell

According to a sworn FBI statement, agents began investigating McDowell after he threatened a synagogue on Facebook.

The statement says McDowell posted statements online praising Roof, but did not appear to have formulated any specific attack plans. Roof faces the death penalty for killing nine black worshippers in a Charleston church.

McDowell doesn't have an attorney. No one answered the phone at his mother's home where he lives.