5:42 PM - WASHINGTON (AP) - Defense officials say the suspected Washington Navy Yard gunman was currently working as a defense department contractor, but it's not clear if he was assigned at the military base in southeast D.C.
Defense officials say Aaron Alexis, 34, of Texas, was working as an information technology contractor, but it was not known which company employed him. As a contractor, he could have had a badge that might have gained him access to the base. Alexis was a former Navy reservist, serving from 2007 to early 2011.
The two officials spoke on condition of anonymity because they were not authorized to discuss it publicly.
Embry-Riddle Aeronautical University also says he was an online student pursuing a bachelor's degree in aeronautics. He started classes in July 2012.
Thirteen people were killed during the shooting rampage at Building 197. More than a dozen others were wounded.
4:45 PM - WASHINGTON (AP) - The White House says President Barack Obama is ordering flags to be lowered to half-staff to honor victims of a shooting at the Washington Navy Yard.
A proclamation Obama signed Monday says flags should be lowered immediately and will remain there until sunset on Friday. The proclamation applies to all public grounds, military posts and naval vessels, plus U.S. embassies and outposts overseas.
Authorities say a former Navy man launched an attack inside a building at the Navy Yard, spraying gunfire on office workers in the cafeteria and in the hallway at the heavily secured installation. Thirteen people were killed, including the gunman.
3:53 PM - WASHINGTON (AP) - The Navy says a gunman who opened fire inside a building at the Washington Navy Yard was a full-time reservist from 2007 to 2011.
The Navy said in a release Monday that 34-year-old Aaron Alexis, of Texas, left the Navy on Jan. 31, 2011, as a petty officer 3rd class. It's not immediately clear why he left.
Alexis had been working for the fleet logistics support squadron No. 46, in Fort Worth, Texas. The Navy says his home of record was New York City.
Alexis was one of 13 people killed during the rampage.
3:25 PM - WASHINGTON (AP) - The D.C. mayor says 13 people have died in the shooting rampage, including the gunman.
Mayor Vincent Gray said at a news conference Monday afternoon that the shooter was among the dead. Officials say the gunman has been identified as 34-year-old Aaron Alexis.
Earlier in the day, authorities had been looking for two other people who may have been involved in the shooting. One of those people has been identified and ruled out as a suspect.
However, Gray says investigators are still searching for a third individual wearing an olive-green, military-style uniform to determine if he was involved.
Gray says a motive has not yet been determined.
3:15PM - WASHINGTON (AP) - Federal law enforcement officials say the man accused in a shooting rampage at the Washington Navy Yard that left at least 12 people dead has been identified 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.
3:12 PM - WASHINGTON (AP) - A hospital official says a police officer and two civilians wounded in the shootings at the Washington Navy Yard are expected to survive.
The shooting rampage left at least 12 people dead.
But the three being treated at Washington Hospital Center are expected to survive. Janis Orlowski, the hospital's chief operating officer, detailed their injuries at a Monday afternoon news conference.
The police officer was still in surgery to treat gunshot wounds to his lower extremities, though Orlowski says he is expected to make a good recovery.
A second victim has a shoulder wound and also is expected to recover.
Orlowski says the third victim being treated at the hospital was shot in the head, but the bullet did not penetrate her skull.
1:19PM - WASHINGTON (AP) - The Senate is postponing scheduled votes until Tuesday in response to the deadly shooting at the Washington Navy Yard.
Moments after the Senate returned to work on Monday, Majority Leader Harry Reid announced that two scheduled votes on nominations would be delayed until Tuesday. The Senate then recessed for the day.
The Senate chaplain, the Rev. Barry Black, has offered a prayer for the victims and their families. Reid and Senate GOP leader Mitch McConnell spoke about the events and expressed their appreciation for the U.S. Capitol Police.
12:30PM - WASHINGTON (AP) - President Barack Obama is mourning what he called "yet another mass shooting" in the United States that he says took the life of American patriots.
Obama promised to make sure, quote, "whoever carried out this cowardly act is held responsible."
He said several people were shot Monday morning at the Washington Navy Yard about 3 1/2 miles from the White House, and some were killed.
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.
The White House says the president has been receiving frequent briefings about the unfolding situation by senior aides.
11:48 AM - CHARLESTON, S.C. (AP) - Vice President Joe Biden says he's been told there may be more than one shooter in a shooting at the Washington Navy Yard.
Biden says the situation is still unfolding, but it's clear a tragedy has occurred. He says he and the White House are praying for the safety of military and police personnel who are trying to bring the situation under control.
Biden says he's been briefed by his national security staff as he's traveling Monday to South Carolina and Georgia.
Officials say six people were killed and at least four were wounded on Monday morning, including a law enforcement officer.
Biden spoke at a port in Charleston during an event highlighting the need to invest in the nation's infrastructure.
11:24 AM - WASHINGTON (AP) - Authorities say they are looking for two additional suspects in the shooting rampage at the Washington Navy Yard.
District of Columbia Police Chief Cathy Lanier says witnesses reported seeing two additional gunmen, both dressed in military-style clothing.
Lanier says one police officer was wounded in an exchange of gunfire with a shooter. She says one shooter has been killed.
Two Navy officials say at least six people were killed in the rampage.
D.C. Mayor Vincent Gray said at a Monday news conference four people were wounded and taken to hospitals.
11:12 AM - WASHINGTON (AP) - Two Navy officials say at least six people have died in a shooting at the Washington Navy Yard.
The officials spoke on condition of anonymity on Monday because they were not authorized to discuss the situation publicly.
A Defense Department official and a federal law enforcement official have said a shooter had died, though it was not immediately clear how.
Police are also looking into the possibility of a second shooter.
As many as 10 were wounded.
10:13 AM -- WASHINGTON (AP) - Two officials say police are looking into the possibility of a second shooter at the Washington Navy Yard where several people were killed.
A Defense Department official and a law enforcement official spoke on condition of anonymity Monday because they were not authorized to discuss the ongoing investigation.
At least one gunman opened fire inside the Naval Sea Systems Command headquarters, where about 3,000 people work just miles from the Capitol.
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.
At least 10 were wounded.
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