Officials have given the all clear at the Washington Navy Yard after the military base was put in lockdown Thursday morning following reports of gunshots heard in a building on the campus.
After a preliminary sweep, authorities reportedly discovered no evidence of a shooting, and said that no arrests had been made, and no weapons found after early morning confusion, a law enforcement official that spoke on the condition of anonymity told reporters. There were also no reports of any injuries.
The US Senate Sergeant at Arms Office also announced an all clear just after 10am Thursday morning.
Earlier Thursday morning, authorities swarmed the area and a heavy police and fire department presence began to amass blocks away from the facility, with roads blocked off and a helicopter hovering overhead.
The Navy Yard, in southeast Washington, is the country's oldest naval installation, and fears of another shooting incident came amid a rise in security concerns in the lead up to the US Independence Day.
In September 2013, military contractor Aaron Alexis killed 12 civilian workers at the same Navy Yard's Building 197 before he was fatally shot by police.
The 2013 shooting spree at the headquarters of the Naval Sea Systems Command (NAVSEA) inside the navy yard was the second-deadliest mass murder on a US military base, second only to the Fort Hood shooting in November 2009.
The Associated Press contributed to this report.