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At around 2:45 p.m., Mayor Adrian Fenty convened a short press conference on the Holocaust Museum shooting. Fenty confirmed that a single shooter entered the main entrance to the Holocaust Museum and immediately opened fire. A security guard returned fire. The gunman was hit. The gunman, who has not been identified officially, has been taken to G.W. Hospital and is in critical condition.

The security guard who was shot is said to be in “grave condition.” He has not been identified.

D.C. Police Chief Cathy Lanier says all information is preliminary but she described the shooter as “what appears to be a lone gunman.”

Lanier goes on to state: “Immediately upon entering, he was engaged by security guards and fire was exchanged.” She added that a city police unit was about a block away when the call went out and responded to the scene. Park Police also responded.

The immediate area around the museum will be closed for “an extended period of time.”

William Parsons, the museum’s chief of staff, says the museum will be open tomorrow. He was clearly distraught over the condition of the security guard. “Never take your guard force and security people for granted,” Parsons said. “They did exactly what they were supposed to do.”

Parsons says the museum was full at the time of the shooting. He estimated the attendance at “a couple thousand.”

Lanier says the area is in the process of being swept by bomb dogs per procedure. She confirmed the gunman was armed with a long rifle and said he did not attempt to conceal it when he entered the museum.

Fenty was asked if this would have an effect on D.C.’s gun laws: “I think that unfortunately these types of things happen throughout the country and throughout the world.”

In closing up the conference, Fenty dubbed this “an extremely isolated incident.”

*By Mike DeBonis.