WASHINGTON, D.C. -
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At least 13 people were killed and many others wounded in Monday's mass shooting at the US Navy Yard in Washington, D.C.
The murdered victims ranged in age from 46 to 73.
Aaron Alexis, the 34-year-old who officials say is responsible for the shooting rampage is dead, D.C. Mayor Vincent Gray confirms.
Officials initially reported as many as two other gunman may have been involved, but D.C. Police Chief Cathy Lanier has now confirmed Aaron is solely responsible.
Alexis was from Fort Worth, Texas and was a military contractor. The FBI confirmed that he had a valid pass for entry to the Washington Navy Yard.
Another dozen or more were wounded, but a hospital official said three shooting victims, including an officer and two civilians, are expected to recover.
Police Chief Cathy Lanier said earlier today there were "potentially two other shooters," a white male and a black male, at large. She said they were wearing military style clothing.
But Monday afternoon, police said a man dressed in a tan, military-style outfit who officials were searching for in connection to the shooting was identified and he isn't believed to be a gunman or involved in incident, the Associated Press reports. He has been ruled out.
The other suspect was described as a black bald man, about 50-years-old. But late Monday night, officials confirm they believe only Alexis was responsible for the mass shooting.
Lanier says people are being told to stay in their homes and out of the area as authorities search for the other possible suspect.
Two police officers are among the wounded. One was injured during an exchange of gunfire, Chief Lanier said.
President Barack Obama described the tragic event as "yet another mass shooting."
Obama promised to make sure, quote, "whoever carried out this cowardly act is held responsible."
He said the victims were "courageous Americans" who knew about the risks of serving overseas, but wouldn't have expected such "unimaginable violence" at home.
Vice President Biden said the shooting is a "God-awful reminder" for Americans to stay vigilant.
Some of the wounded are in critical condition, said Janis Orlowski, Chief Medical Officer at Washington Medical Center, said earlier in the day.
"They have severe injuries, but are conscious," she said. "We have three individuals, but we are told to expect more." Those three individuals Orlowski referred to, an officer and two civilians are in critical but stable condition. One of the victims, a woman, is said to be "very lucky" she is okay.
Orlowski said some victims died at the scene of the shootings, but she did not have an exact number.
The shootings occurred at the Naval Sea Systems Command Headquarters around 8:20 a.m.
A shelter-in-place order was issued.
Two people provided eyewitness accounts to CNN. One female eyewitness, who identified herself as Terry Durham, said she was with a group of people when they spotted the gunman.
She said he aimed what appeared to be a rifle in their direction and fired. "He hit high on the wall," she said. “He was tall. He appeared to be dark-skinned."
She said the group escaped safely.
Another witness, Patricia Ward, told WUSA "I was going to the cafeteria to get something to eat and I heard 'pow pow pow."
Six area schools were placed on lockdown. Security at the Pentagon was tightened.
A ground stop was initiated at Reagan National Airport for several hours because of the shooting, according to WJLA.
The Naval Sea Systems Command's headquarters is the work place for about 3,000 people, according to the Network News Service.
Naval Sea Systems Command (NAVSEA) is the largest of the Navy's five system commands.
The organization is comprised of command staff, headquarters directorates, affiliated Program Executive Offices (PEOs) and numerous field activities. With a fiscal year budget of nearly $30 billion, NAVSEA accounts for one quarter of the Navy's entire budget.
With a force of 60,000 civilian, military and contract support personnel, NAVSEA engineers, builds, buys and maintains the Navy's ships and submarines and their combat systems.
The Washington Navy Yard says on its website that it's the Navy's oldest shore establishment. It's home to the chief of Naval Operations and is also headquarters for the Naval Historical Center and numerous naval commands.
The Navy Yard is several miles from the White House and Capitol Hill.
THIS IS A DEVELOPING STORY. MORE TO COME.
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