This booking photo provided by the Fort Worth Police Department shows Aaron Alexis, arrested in September, 2010, on suspicion of discharging a firearm in the city limits. The FBI has identified Alexis, 34, as the gunman in the Monday, Sept. 16, 2013 shooting rampage at at the Washington Navy Yard in Washington that left thirteen dead, including himself.WASHINGTON - An official says shots have been reported in a building on the Washington Navy Yard campus.
Navy spokesman Petty Officer 1st Class Pedro Rodriguez says a lockdown is underway.
He did not give information on injuries or other details Thursday morning.
In September 2013, military contractor Aaron Alexis killed 12 civilian workers at the Navy Yard's Building 197 before he was fatally shot by police.
The Navy Yard, in southeast Washington, is the country's oldest naval installation.