"It is one of many parasitical Rothschild Central Banks infesting the world stage," he wrote on www.holywesternempire.org. "Its power ascends over every U.S. citizen from cradle to grave. Every dollar in your wallet is a note issued by the FED. The U.S. Government redeems that note (principal and interest) with your taxes. Through its enormous resources and power the FED controls the machinery of the U.S. Government."
A neighbor in Maryland described von Brunn as a standoffish man who didn't socialize with neighbors. The neighbor expressed shock upon hearing von Brunn had been identified as the alleged shooter.
"My God, I live next to that man," Harold O'Lynnger, 82, told ABC News.
O'Lynnger recalled a comment von Brunn had made over drinks three months ago that the media had been giving the Holocaust too much attention.
A statement by museum director Sara Bloomfield, obtained by ABC News, confirmed the death of the security guard and said: "There are no words to express our grief and shock over today's events."
"It is my sad duty to inform you of the passing of Officer Stephen Tyrone Johns, who died heroically in the line of duty today," Bloomfield continued. "He served on the Museum's security staff for six years. Our thoughts and prayers go out to Officer Johns' family."
Bloomfield said that the museum will remain closed Thursday in honor of Johns.
Johns' son, Stephen T. Johns Jr., told reporters that his father "was a loving father and he was my hero."
The victim's stepfather, Leroy Carter, described Johns as a "responsible human being," and said that with Johns' job at the Holocaust Museum, he "didn't have to worry about the line of work" his stepson was in. Carter didn't think the job would be dangerous but said it "backfired."
Carter said he found out about the shooting on the radio and called his wife and Johns' wife. He also informed Johns' namesake son.
President Obama released a statement Wednesday evening honoring Johns and calling for vigilance against prejudice.
"I am shocked and saddened by today's shooting at the U.S. Holocaust Memorial Museum," Obama's statement read. "This outrageous act reminds us that we must remain vigilant against anti-Semitism and prejudice in all its forms. No American institution is more important to this effort than the Holocaust Museum, and no act of violence will diminish our determination to honor those who were lost by building a more peaceful and tolerant world.
"Today, we have lost a courageous security guard who stood watch at this place of solemn remembrance," Obama added. "My thoughts and prayers are with his family and friends in this painful time."
Von Brunn allegedly entered the museum with a .22-caliber rifle and exchanged gunfire with Johns, law enforcement officials said. Two other guards returned fire and wounded the alleged gunman.
The incident took place just before 1 p.m. ET, D.C. Metro Police Chief Cathy Lanier said.
Ambulances transported both wounded men to George Washington University Hospital in Washington. Medical personnel treated a third person hurt by glass at the scene of the incident.