As novel coronavirus cases continue to spread among the ranks, top officials and health leaders have emphasized that the military must take crucial steps to help stop it, including new health-protection conditions (HPCON) and increased social distancing measures on bases.

But photos taken just last week show troops training side by side or participating in large gatherings amid the COVID-19 outbreak.

Publicly released military photos show service members participating in drill exercises and live-fire training, among other activities that require them to operate in close proximity.

The commanding officer of the USS Green Bay speaks to sailors and Marines during an all-hands call, March 13, 2020. (U.S. Navy/Mass Communication Specialist 3rd Class Maria G. Llanos)

The U.S. military services began taking precautions as early as March 7. Some services and commands attempted to limit human contact as much as possible with telework and virtual meetings, while others began canceling events and overseas travel. The protective measures even applied to brand-new service members as the Army, Navy, Air Force, Marine Corps and Coast Guard began screening all new recruits for coronavirus symptoms earlier this month to prevent potential spread throughout the force, officials confirmed to Military.com on March 4.

Related: Tell Us: Is Your Command Doing Enough to Stop the Spread of Coronavirus?

This week, Defense Secretary Mark Esper said that, while social distancing may be impossible inside a tank or on a submarine, "If you can avoid putting ... a large number of people in small rooms, you should do it."

Marines fire M4 carbine and M16A4 rifles during a live-fire training range aboard the USS New York, March 20, 2020. (U.S. Marine Corps/Staff Sgt. Patricia A. Morris)

"Hold your meeting outside, and maybe meet in smaller groups," he said at a Pentagon town hall Tuesday. "If you're a young NCO or young officer and you see something that doesn't make sense, raise it privately with your chain of command and say, 'Hey, maybe we should do this differently next time.'"

Esper approved another guidance Wednesday that expands on an earlier 60-day overseas travel prohibition for troops, their accompanying family members and Defense Department personnel.

The new instruction essentially blocks all U.S. personnel from any international travel; those scheduled to return from deployments or overseas tours, rotations and exercises could be stuck in place until late May.

A sailor carries a machine gun mount aboard the USS Bataan, March 19, 2020. (U.S. Marine Corps/Cpl. Gary Jayne III)

Earlier Wednesday, a top Defense Department medical officer stressed that the military, much like the general population, should not downplay the seriousness of the pandemic, which has affected troops, dependents, contractors and DoD civilians.

"Our curve is not flattening, and that's why we went to HPCON-Charlie today, which includes restrictions on large gatherings and includes additional social distancing," said Air Force Brig. Gen. (Dr.) Paul Friedrichs, the Joint Staff surgeon, referring to the increased protection level at military installations.

HPCON-C raises health protection measures where the situation encompasses "high morbidity epidemic or contamination," according to a DoD graphic.

An Airman gets coined for excellence during at Cargo City, Kuwait, March 17, 2020. (U.S. Air Force/Tech. Sgt. Alexandre Montes)

"We're stepping through this like everyone else is and adjusting based on the data that's coming in and what we're seeing with our units," Friedrichs said. "[What] I would recommend is, as we step through this, we take the most appropriate precautions today for what we know is happening right now.

"What we don't want to do is build either a false sense of anxiety or concern or a false sense of security. What we know right now is, this is a very significant outbreak. It's a global pandemic. What we need to do is make sure that we're minimizing contact, [and] people are staying home when they can stay home," he said.

The Pentagon on Thursday said it had 280 military cases of coronavirus, an increase of 106 cases since Tuesday. Of those, 15 service members have been hospitalized, it added.

In an interview with Reuters, Esper said that, while the Pentagon will provide broad data on how the virus spreads throughout the ranks, officials will hold back on more granular, mission-specific data in an effort to preserve operational security.

“What we want to do is give you aggregated numbers,” the secretary told the news outlet Wednesday. “But we’re not going to disaggregate numbers because it could reveal information about where we may be affected at a higher rate than maybe some other places.”

-- Gina Harkins contributed to this report.

-- Oriana Pawlyk can be reached at oriana.pawlyk@military.com. Follow her on Twitter at @Oriana0214.

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