This week in Washington (42 images)

With the U.S. Capitol in the background, the flags at the Washington Monument and World War II Memorial (R) fly at half-staff on Thursday, in honor of the 17 high school students and teachers that were killed in a mass shooting at a Florida high school yesterday. More than a dozen were injured. A former student used an AR-15 assault rifle that is based on the U.S. Military M16 automatic weapon. Photo by Pat Benic/UPI

With the Lincoln Memorial in the background the flags at the World War II Memorial fly at half-staff. Photo by Pat Benic/UPI

A staff member leaves the roof of the White House after lowering the flag to half staff to honor the victims of the recent high school mass shooting in Florida on Thursday. Photo by Pete Marovich/UPI

President Donald Trump addresses the nation about Wednesday's mass shooting from the Diplomatic Room of the White House on Thursday. Trump said he is planning a visit to Parkland, Florida. Photo by Pete Marovich/UPI