At least 12 dead, suspect sought in shooting of Navy.

Hunt is underway for two gunmen increasingly possible after at least 12 people were killed and several others were injured Monday at the headquarters of the Royal Navy at sea system command at Washington Metropolitan Police Chief Cathy Lanier . said.

Lanier said police shot dead and one wounded in the " engagement " with at least one gunman . She said staff had created "a lot " of information that would have been more gunmen .

Lanier , who said that the FBI is now leading the investigation , said the motive for the shooting has not been determined.

She said officials are looking for a white male wearing a brown short-sleeved uniform , beret and military hand gun . Police are also looking for a black man between 40 and 50 years old wearing a bright olive military uniform and carrying a rifle, Lanier said .

She said there was no evidence the suspect officers .

Law enforcement official said federal authorities had interviewed a man whose identity emerged after police killed the gunman, armed with AR-15, a shotgun and a sniper if handgun.The human connection . there was not immediately clear.

Federal official who requested anonymity because of the fluid nature of the investigation, said there was no evidence that anyone other than the gunmen fired weapons in the attack. The official said that the researchers analyzed surveillance video and other information that reveals the two men - one white male and one black - both dressed in military -style uniforms .

"What we lack is targeting someone other than the shot ,'' the official was not authorized to comment publicly said.

At least 12 dead, suspect sought in shooting of Navy.