At least one person was injured Monday after a person fired shots inside the Washington Navy Yard, the US Navy said. An official told CNN that "several" people sustained injuries.

The incident occurred at 8:20 a.m. Authorities say there is an "active shooter" on the scene.

Several shots were fired at the Naval Sea Systems Command headquarters, in southeast Washington, D.C., the Navy said.

The Navy first informed the public of the incident in a Twitter message.

Emergency personnel were on the scene and a "shelter in place" order has been issued for Navy Yard personnel.

The headquarters -- the workplace for about 3,000 people -- is the largest of the Navy's five system commands.

Picture of the naval yard tweeted by @bikepedantic