Frederick Police said just before 9 a.m.in a tweet that the shooting happened in the 8400 block of Progress Drive. Police say they've responded to an active shooter and that there are a couple of victims.
Shortly thereafter, police learned that the suspected gunman, a 38-year-old male, "traveled to the Fort Detrick military base" and was shot by "personnel on the base". The victims were flown by helicopter to Baltimore and are in critical condition, Lando said.
The press conference came moments after the U.S. Navy confirmed to the Associated Press Tuesday that an "active shooter incident" took place at Fort Detrick - a nearby Army base - and that sailors were involved in the incident.
"The public is no longer at risk".
Jeremy Mutschler, director of marketing for Nicolock Paving Stones, said that his understanding is that the shooting was near the company's Frederick location but not at the business itself.
Special agents with the Bureau of Alcohol, Tobacco, Firearms and Explosives are responding to assist, the ATF's office in Baltimore said on Twitter.