James von Brunn, an 88-year-old white supremacist from Maryland, has been taken into custody following a shooting at the U.S. Holocaust Memorial earlier today.

Sergeant David Schlosser, a spokesman for U.S. Park Police, said a man armed with a “long gun” entered the museum at 12:50pm and fired at a security officer, resulting in both being wounded in an exchange of gunfire.

“My understanding is that two other security officers at the museum returned gunfire at the man that had entered the museum,” Schlosser said.

Schlosser said he didn’t know exactly what kind of firearm the man had and whether the shooting was before or after he passed through a metal detector.

A witness said she heard five shots and saw a security guard lying wounded on the ground.

“It was definitely a security guard, he was down bleeding on the floor,” she said. “He was face down. His back … blood was coming out.”

Sergeant Schlosser said the security guard that was initially shot and the gunman have been transported to George Washington University Hospital but he didn’t know their conditions.