Washington, September 16 
Three gunmen today went on the rampage in the high-security Washington Navy Yard, located a short distance from the White House, killing 12 persons and injuring several others in an audacious mass shooting.

One of the gunmen was shot dead and the police said it was looking for other two gunmen who were believed to be at large and dressed in military-style clothing.

At least 12 persons were killed in the shooting, Washington DC Mayor Vincent Gray and police chief Cathy Lanier said. "We are confirming 12 fatalities. We had a few additional victims who were injured. They were not fatally injured," Lanier said.

"Right now, we have multiple pieces of information to suggest that we had at least two other persons seen with firearms. These persons, we believe, are involved in some way," Lanier said. "The first is for a white male between 40 and 50 years of age... wearing military uniform consistent with a naval uniform and a beret style hat," she said. "We also have a lookout for a black male between the ages of 40 and 50 in an olive military style uniform."

Earlier, Lanier told a news conference that one of the shooters was dead and authorities were searching for a white man and a black man. "The big concern for us right now is that we have potentially two other shooters that we have not located at this point," Lanier said.

"We have no information to believe that either of these folks are military personnel, but we do have information that those individuals are wearing military-style uniforms," she said. Lanier said there is no indication of a possible motive at this time.

Speaking at the White House, President Barack Obama called for a seamless investigation by federal and local authorities and promised to bring those responsible for the attack to justice. Terming it "yet another mass shooting" in the US, Obama said his administration would make sure that "whoever carried out this cowardly act is held responsible." — PTI