Washington (CNN) There are now 25 sailors who have tested positive for the coronavirus aboard the aircraft carrier USS Theodore Roosevelt, just two days after the Pentagon announced that three sailors aboard the ship had tested positive for the virus, a Navy official has confirmed to CNN.

The Navy says they expect there to be additional positive tests among the crew, with one official telling CNN there could possibly be "dozens" of new cases that emerge. A second official said that were there to be a large number of additional cases, the Defense Department would be unlikely to publicly specify how many of the Navy's overall cases are amongst members of the crew of the Roosevelt, due to concerns that adversaries such as China or North Korea could see the ship as vulnerable.

Despite the outbreak, Chief of Naval Operations Adm. Mike Gilday said in a statement, "we are confident that our aggressive response will keep USS Theodore Roosevelt able to respond to any crisis in the region."

Earlier in the day, acting Navy Secretary Thomas Modly had said there were "several" more cases onboard the ship, but did not give a specific number.

"We are in the process now of testing 100% of the crew of that ship to ensure that we're able to contain whatever spread might've occurred," Modly told reporters at the Pentagon at a briefing Thursday morning. There are approximately 5,000 personnel on board the carrier.

ROSLAN RAHMAN/AFP/Getty Images

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