Chelsea J. Carter and Brian Todd
WASHINGTON (CNN) — There are more questions than answers about who was behind Monday’s rampage at the Washington Navy Yard as law enforcement authorities confirmed at least one gunman was dead and the search was on for at least one other possible suspect.
Authorities say at least 12 people were killed in a rampage at the headquarters for Naval Sea Systems Command in southeast Washington, where witnesses described a terrifying, chaotic scene that began unfolding at 8:15 a.m. ET.
“We have no known motive at this stage. There were people who asked earlier if this was a terrorist event. We don’t have any reason to think that at this stage. But we are continuing that investigation to try to determine what the motive is.,” Mayor Vincent C. Gray told reporters.
“We also don’t know for certain if there are other shooters,” he added.
This much is known: A gunman is dead, Cathy Lanier, the chief of the Metropolitan Police Department, told reporters.
Police also have cleared one of at least two people they were looking for in connection with the shooting. That man, a white male wearing a Navy uniform, “has been identified and is not a suspect or person of interest,” Metropolitan Police said in a post on Twitter.
Authorities are, however, looking for an African-American male, between 40 and 50, with a medium complexion and gray sideburns who was reportedly wearing an “olive drab-colored” military-style uniform, Lanier said.
He was believed to be carrying, what Lanier described, as a “long gun.”
Lanier did not rule out whether the suspects were military personnel. She also would not say whether the dead gunman had been identified or whether he was a military service member.
While the police chief would not say why authorities believe there may be others involved, witnesses have given CNN and other news organizations several descriptions that indicate there may have been more than one shooter.
President Barack Obama reacted to the shooting that erupted inside Building 197, causing confusion and panic at the historic post.
“We will do everything in our power to make sure whoever carried out this cowardly act is held responsible,” Obama said, adding the shooting “targeted military and civilian personnel.”
Two people told CNN affiliate WJLA that they heard a fire alarm go off in the building where they worked and then saw a tall African-American man with a rifle down the hallway as they exited the building.
“He aimed the gun and fired our way,” a man who identified himself as Todd Brundidge told WJLA, adding, “I couldn’t believe it.”
CNN’s Brian Todd reported from Washington, and Chelsea J. Carter reported and wrote this report from Atlanta. CNN’s Barbara Starr, Jake Tapper, Alan Silverleib, Dan Merica, Larry Shaugnessy and Evan Perez contributed to this report.