One gunman, and possibly a second, opened fire Monday inside one of the Navy's oldest buildings, attacking office workers at a heavily guarded military facility in the heart of the nation's capital. Thirteen people were killed and several others — including two police officers — were wounded.
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Mayor Vincent Gray said authorities still don’t know the motive behind the shooting.
“We don’t have any reason at this stage to suspect terrorism, but certainly it has not been ruled out,” he said.
One of the gunmen was dead. Federal law enforcement officials identified him as Aaron Alexis. The two officials spoke Monday to The Associated Press on condition of anonymity because they were not authorized to speak publicly.
One of those officials says Alexis was a 34-year-old from Texas. He is believed to have a criminal record there and to be a holder of a concealed-carry weapon permit.
That official says Alexis is believed to have gotten into the Navy Yard by using someone else's identification card. It is not yet clear if that individual was an accomplice or if that person's ID card was stolen.
Police initial said they were searching for two other men believed to have joined in the attack. A possible third suspect was identified Monday afternoon and cleared, police said.
The remaining possible suspect reportedly was disguised in olive-green military-style clothing, and said to be carrying a long gun, D.C. Police Chief Cathy Lanier said.
Investigators said they had not established a motive for the shooting rampage, which unfolded less than four miles 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 shootings began about 8:20 a.m.
President Barack Obama was getting frequent briefings on the shootings, and in remarks Monday afternoon, called the shooting victims "patriots." Targeting military personnel and civilians, he said, is a "cowardly" act. He described the shootings as an act of "unimaginable violence."
The FBI has taken the lead role in the investigation.
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.
As witnesses emerged from the building, a helicopter hovered over the building, schools were on lockdown and airplanes at nearby Reagan National Airport were briefly grounded.
CNN reported an increase in security at the Pentagon and other military installations in the Washington area.
Less than two miles away, security was beefed up at the Capitol. The Senate and its adjacent office buildings were locked down, the Senate sergeant at arms announced.
Monday night's baseball game between the Washington Nationals and the Atlanta Braves was postponed because of the proximity of the stadium, Nationals Park, to the Navy Yard.
DC police were using the stadium parking lot as a location to reunite families with those who work at the Navy Yard.
The conditions of those wounded were not immediately known.
About 3,000 people work at the Naval Sea Systems Command headquarters, which builds, buys, and maintains the Navy's ships, submarines and combat systems. The Washington facility is the largest of the Navy's five system commands and accounts for a quarter of the Navy's entire budget.
Todd Brundidge, an executive assistant with Navy Sea Systems Command, said he and other co-workers encountered a gunman in a long 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 with the same agency, said she also saw the gunman firing toward her and Brundidge.
"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.
Shortly after the gunfire, Mason said someone on an overhead speaker told workers to seek shelter and later to head for the gates at the complex.
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."
Ward said security officers started directing people out of the building with guns drawn.
Police and federal agents from multiple law enforcement agencies responded. Ambulances were parked outside, streets in the area were closed, and departures from Reagan National Airport were temporarily halted for security reasons.
Among the wounded was a D.C. police officer, according to a law enforcement official who spoke on the condition of anonymity because the person was not authorized to discuss an ongoing investigation.
A U.S. Park Police helicopter hovered over the building and appeared to drop a basket with a person onto the roof.
Officials at MedStar Washington Hospital Center said three shooting victims had been brought there and were in critical condition..
District of Columbia schools officials said six schools and one administrative building in the vicinity of the Navy Yard were placed on lockdown. The action was taken due to an abundance of caution, schools spokeswoman Melissa Salmanowitz said.
The Navy Yard is part of a fast-growing neighborhood on the banks of the Anacostia River in southeast Washington, just blocks from Nationals Park baseball stadium and about 1½ miles southeast of the U.S. Capitol.
It houses a museum and the residence of the chief of naval operations, and is responsible for weapons development, among other functions. No other Navy installations have been locked down because of the situation in Washington, the Navy said.
The Washington Post reported
that gunfire was heard about 11 a.m., and also that one of the heavily armed shooters was "down." One shooter reportedly was dressed in black and was armed with an assault rifle.
The Post reported there were up to three shooters, one dressed in military fatigues.
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