UPDATE 1:43 P.M.
Radio station WTOP is reporting that D.C. police say a person walked into the museum and shot a security guard shortly before 1 p.m. Police told the station that two other security guards returned fire, injuring the gunman. The injured security guard and shooting suspect have been taken to the hospital.
WASHINGTON D.C. (CBS) Washington D.C. police tell CBS News there are reports of gunfire around the Holocaust Museum. FBI has confirmed shots were fired. Developing...