They identified him as Fantahun Girma Woldesenbet, whose rank was E-4.
“We are still investigating the motive, investigating the exact circumstances,” the army brigadier said. General Michael J. Talley told reporters at an afternoon press conference.
The gunman was stopped at the gates of the post, but before the vehicle could be searched, the gunman took off. He was stopped about 1/2 mile out of the facility, where he got out of the car, brandished a gun and was shot by police, Talley told reporters.
Frederick Police Chief Jason Lando said the first shooting took place at “a military institution” in Riverside Tech Park. In a press release, the police department said the building was a warehouse rented by the Naval Medical Research Center of the Biological Defense Research Directorate to store research supplies and equipment.
The chief said the shooter used a rifle but did not provide any additional information about the weapon.
One victim is in critical condition but is stable in a hospital. The second victim is in serious condition but will likely be released on Wednesday. The two were removed from the scene by helicopter, police said.
The police were called around 8:20 a.m.
After the shooting, a victim walked into a nearby business, Nicolock Paving Stones, and called for help, a person said.
“Our team was able to help them and called the authorities,” read a statement issued by Jeremy Mutschler, director of marketing and advertising at Nicolock. The statement points out that the shooting did not take place in Nicolock.
Agencies helping Frederick’s police include the FBI; the Bureau of Alcohol, Tobacco, Firearms and Explosives; Maryland State Police; and the Frederick County Sheriff’s Office.
The FBI is handling the first scene of filming, officials said.
Frederick is approximately 50 miles northwest of Washington, DC. Woldesenbet did not live in Fort Detrick, officials said.
CNN’s Joe Johns, Amanda Watts and Michael Callahan contributed to this report.