WASHINGTON — A lockdown is underway on the entire Washington Navy Yard campus after a report of shots fired.

A federal official said there were reports of shots fired today in the same building where a gunman killed a dozen workers in a rampage two years ago. The official, speaking on condition of anonymity because the official wasn’t authorized to discuss details publicly, said there are no reports of injuries nor has a shooter been identified.

A police and fire department presence began blocks away, with roads blocked and a helicopter overhead.

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 building has since been renamed the Humphreys Building. It reopened this year.