One Navy Yard Shooter Killed, Manhunt Under Way for One More Suspect (UPDATE: 12 Dead)

WASHINGTON -- The chief of the D.C. police said there are still two potential shooters on the loose after one was killed in the mass shooting at the Navy Yard this morning.

Chief Cathy Lanier said that the first call on the shooting came in at 8:15 a.m.

D.C. Mayor Vincent Gray said responding officers "engaged at least one person along the way" and that four wounded were taken from the scene.

"We're still trying to confirm the number of fatalities involved," Gray said. "...As far as we know, this was an isolated incident."

Lanier said they have "one shooter that we believe involved in this that is deceased." The department is also accounting for "multiple victims inside that are deceased."

"The big concern," she said, is two more potential shooters "that we have not located at this point."

One is described as a white male in his 40s in a khaki military uniform with short sleeves and a beret hat. Lanier said he was last seen at 8:35 a.m. with a handgun. The other is a 5'10" black male, about 50 years of age with gray sideburns, in an olive-drab-colored, possible military-style uniform, carrying a long gun, the chief said.

"We have no information to believe that either of those individuals are military personnel," Lanier added.

The White House refused to cancel a lunchtime event marking five years since President Obama put financial-crisis policies in place.

Backdropped by handpicked Americans and saying financial recovery is well under way, Obama opened his comments lauding Obamacare and slamming the rich with a nod to the shooting.

"We're confronting yet another mass shooting," Obama said. He added the victims are "patriots" who "know the dangers of serving abroad, but today they face the unimaginable violence that they wouldn't expect at home."

"Obviously we're going to be investigating … as we do so many of these shootings," Obama said.

UPDATE: Lanier just held a press conference updating the death toll to 12, and a "few additional folks that were injured."

"I think the actions by the police officers without question helped to reduce the number of lives lost," she said.

The be-on-the-lookouts for the two suspects are still in force. Text alerts have been sent to residents in the area asking them to stay out of the neighborhood until further notice.

"These are people that we really believe are involved in some way," the chief said of the suspects. She said the belief that there are still suspects came from "multiple" sources.

Police are keeping details about the shooter who was killed under wraps. "There are very, very few questions we can answer at this point," Lanier said.

"We've not had a day like this since 9/11 for good reason," D.C. Del. Eleanor Holmes Norton (D) said at the scene. "...I'm really asking everyone to withhold judgment about what happened here."

UPDATE: The white male has been eliminated as a suspect, per police.

Multiple outlets are reporting that law enforcement officials identified the dead shooter as Aaron Alexis, 34, of Fort Worth, Texas. He recently began working in the area as a civilian contractor. Some outlets are reporting that he used another employee's access card.

An Aaron Alexis of the same age was arrested in 2010 for reckless discharge of a firearm.

The FBI has taken control of the investigation.