UNITED STATES - Tags: CRIME LAW MILITARY
A U.S. Park Police officer moves bystanders back from the scene of a shooting at the Washington Navy Yard in Washington, September 16, 2013. The U.S. Navy said several people were injured and there were possible fatalities in the shooting at the Navy Yard in Washington D.C. on Monday. The Navy did not immediately provide additional details but a Washington police spokesman said earlier that five people had been shot, including a District of Columbia police officer and one other law enforcement officer. REUTERS/Jason Reed (UNITED STATES - Tags: CRIME LAW MILITARY) - RTX13NGQ REUTERS
As many as two gunmen opened fire Monday morning inside the Washington Navy Yard, killing at least 13 people in an attack on office workers at the heavily secured military installation in the heart of the nation's capital, authorities said.
The number of dead included a gunman. Police said they were hunting for a second possible attacker who may have been disguised in a military-style uniform.
Authorities identified the dead shooter as a navy employee whose work status had been changed earlier this year, said a federal government official who spoke only on condition of anonymity because he wasn't authorized to speak on the record. The dead gunman was identified as 34-year-old Aaron Alexis, a former resident of Fort Worth, Texas.
Investigators said they had not established a motive for the shooting rampage, which unfolded less than seven kilometres from the White House. As for whether it may have been a terrorist attack, Mayor Vincent Gray said: "We don't have any reason to think that at this stage."
The FBI took charge of the investigation.
U.S. President Barack Obama mourned yet another mass shooting in the U.S. that he said took the lives of American patriots. Obama promised to make sure "whoever carried out this cowardly act is held responsible."
Officials said as many as a dozen others were wounded — three critically — in the rampage at the Washington Navy Yard, including a law enforcement officer.
- Washington residents post from scene of Navy Yard shooting
The shooting led to tightened security at the Capitol and White House nearby. The U.S. Senate was being shut down as a precaution and the Washington Nationals baseball club cancelled Monday night's game with the Atlanta Braves.
D.C. Police Chief Cathy Lanier said people were being told to stay in their homes and out of the area.
Witnesses described a gunman opening fire from the fourth floor, aiming down on people in the first-floor cafeteria. Others said a gunman fired at them in a third-floor hallway.
Schools were on lockdown, and airplanes at nearby Reagan National Airport were briefly grounded.
About 3,000 people work at the Naval Sea Systems Command headquarters, which builds, buys and maintains the navy's ships and submarines and combat systems.
Todd Brundidge, an executive assistant with Navy Sea Systems Command, said he and other co-workers encountered a gunman in a hallway of their building on the third floor. The gunman was wearing all blue, he said.
"He just turned and started firing," Brundidge said.
Terrie Durham, an executive assistant, said she also saw the gunman firing toward her and Brundridge.
"He aimed high and missed," she said. "He said nothing. As soon as I realized he was shooting, we just said, 'Get out of the building."'
Rick Mason, a program management analyst who is a civilian with the U.S. navy, said a gunman was shooting from a fourth-floor overlook in the hallway outside his office. He said the gunman was aiming down at people in the building's cafeteria on the first floor. Mason said he could hear the shots but could not see a gunman.
Patricia Ward, a logistics management specialist, said she was in the cafeteria and heard shots. They sounded like "pop, pop, pop," she said. After a few seconds, there were more shots.
"Everybody just panicked at first," she said. "It was just people running, running, running."
Jacqueline Alston says she hasn't heard from her common-law husband Ernest Johnston, who works as a cleaner in building 197 at the navy yard.
"I'm just worried sick," she told the CBC's Meagan Fitzpatrick. "I want him to call me."
"I'm numb," she said, holding back tears. "Just come on home, baby," she said, when asked what message she has for her husband. He's worked at the navy yard since 2008.
"They told me to be patient," she said.
Families have been told to gather at the National Stadium for further information.