A gunman opened fire today at a navy facility in Washington D.C., wounding about a dozen people.

Injured lay on the ground, and are now being airlifted to hospitals.

SWAT teams swarmed the facility, the headquarters of the Naval Sea Systems Command at the Washington Navy Yard.

At least four people have been killed and eight more wounded. The shooter was also wounded.

Go to cbsnews.com for the latest emerging details.