(Updates with exposure of top Army commander in Europe)

By Phil Stewart

WASHINGTON, March 9 (Reuters) - The top U.S. Army commander in Europe may have been exposed to the coronavirus, while a Marine who tested positive for it had been working for a defense agency close to the Pentagon, officials said on Monday.

The disclosures show the risks to the U.S. military even as it tries to limit the fallout from the global virus outbreak on the more than a million active-duty troops around the world.

In the case of Lieutenant General Christopher Cavoli, the possible exposure took place during a conference with land force commanders in Europe on Friday in Wiesbaden, Germany. In a photo, Cavoli is pictured sitting next to an unnamed Italian military officer whose face cannot be seen in a military photo of the event https://www.dvidshub.net/image/6129417/land-force-commanders-allied-nato-and-partner-nations-meet-discuss-defender-europe-20.

Reuters reported on Sunday that Italian army Chief of Staff General Salvatore Farina contracted the virus.

The U.S. Army declined to say who may have exposed Cavoli to the virus inadvertently or whether Farina was at the conference.

The Pentagon said seven cases were under investigation and that three active-duty service members so far had tested positive for the virus. Beyond the Marine, they include previously reported cases of a soldier in South Korea and a sailor in Italy.

U.S. officials told Reuters that the Marine worked at the Defense Security Cooperation Agency (DSCA), which helps oversee foreign military sales and international military educational partnerships. The Marine had returned last month from Ethiopia.

He is being treated at a military hospital at Fort Belvoir, Virginia, in the Washington suburbs. The Marine was living with his family at Marine Corps Base Quantico, which said in an online post that base schools were being closed until Wednesday to allow time for a thorough cleaning.

The base said his family and personnel in contact with him "have been identified and do not show symptoms."

It was unclear whether the DSCA, which is headquartered in Crystal City, Virginia, was taking any precautionary steps since the Marine tested positive for the virus.

Air Force Brigadier General Paul Friedrichs, the senior health official for the Joint Chiefs of Staff, said he was not aware of any visits by the Marine to the Pentagon.

Defense Secretary Mark Esper is expected to approve additional steps in the coming days to better safeguard the Pentagon, one of the world's largest office buildings, where some 22,000 people work everyday.

Esper held a regular morning meeting with senior leaders on Monday partly by using videoconferencing technology - so that conference rooms were not as packed with people, the Pentagon said.

"The effort this morning was to show that we can continue to do this while practicing risk-prevention measures," Pentagon spokesman Jonathan Hoffman said. (Reporting by Phil Stewart; Editing by Jonathan Oatis and Peter Cooney)

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