FREDERICK, Md. — An Army official says the two people shot in Frederick, Maryland, were both sailors in the U.S. Navy assigned to Fort Detrick.

Brigadier General Michael J. Talley released the information at a news conference, and police identified the suspect as Fantahun Girma Woldesenbet, 38, a Petty Officer Third Class assigned to Fort Detrick who lived off-base in Frederick.

Frederick Police Chief Jason Lando said Woldesenbet used a rifle in the shooting at a Navy-related facility in the office park.

He entered a business at the Riverside Tech Park, causing people inside to flee, Lando said.

After the shooting, the medic drove about 10 minutes to Fort Detrick, where he was shot by base personnel, Lando said at a news conference. The two people who were critically wounded by the shooter were airlifted to a hospital, he said. A spokeswoman for Shock Trauma at the University of Maryland Medical Center in Baltimore did not immediately respond to an email asking for an update on their conditions.

The medic drove through a gate at the entrance to the base but only got about a quarter of a mile before he was stopped by military personnel, said Fort Detrick spokeswoman Lanessa Hill. She said Frederick police had given base officials advance notice, "so we knew that he was out there."

Fort Detrick is home to the military's flagship biological defense laboratory and several federal civilian biodefense labs. About 10,000 military personnel and civilians work on the base, which encompasses about 1,300 acres (526 hectares) in the city of Frederick.

The base is a huge economic driver in the region, drawing scientists, military personnel and their families. Frederick Mayor Michael O'Connor noted that various defense contractors are located near Fort Detrick and that it wouldn't be unusual for a member of the military to be off base and working with a private firm that does business with the U.S. government.

"When these incidents happen in other places, you're always grateful that it's not your community," O'Connor added. "But you always know, perhaps in the back of your mind, that that's just luck — that there isn't any reason why it couldn't happen here. And today it did."

By early afternoon, the Nallin Farm gate at Fort Detrick through which the shooter entered remained closed and two officers were standing by.

Mark Nelson, a firefighter who lives in a row of townhomes across the street from the base, said he heard the base blast warning sirens Tuesday morning.

"I heard, I don't know what they call it, but they were like air raid sirens, and I knew something was going on," Nelson said.

Lando called the shootings "very tragic."

"It's happening too frequently," he said. Every time we turn on the TV we're seeing something like this happening. And now it's happening in our backyards."

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This story has been edited to correct that base personnel, not police, shot the suspect and to correct a word in the base spokeswoman's quote to "after," not "before." ___

Associated Press writers Matthew Barakat in Frederick; Michael Kunzelman in College Park, Maryland; Ben Finley in Norfolk, Virginia; Jonathan Drew in Durham, North Carolina, contributed to this report.

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