A son of the 88-year-old white supremacist who allegedly started a shootout at the U.S. Holocaust Memorial Museum is slamming his father's "cowardice" and apologizing to the family of the security guard his dad is accused of killing.

"For a long time, I believed this was our family's cross to bear," he added. "Now, it is not only my families lives that are in shambles, but those who were directly affected by his actions; especially the family of Mr. Johns, who bravely sacrificed his life to stop my father.

"For the extremists who believe my father is a hero: it is imperative you understand what he did was an act of cowardice," Erik von Brunn wrote. "To physically force your beliefs onto others with violence is not brave, but bullying. Doing so only serves to prove how weak those beliefs are. It is simply desperation, reminiscent of a temper tantrum when a child cannot get his way. Violence is a cop out; an easy answer for an ignorant problem."