Most of the seafarers aboard the U.S. Navy’s guided missile destroyer Chafee have been quarantined on the crew after a COVID-19 outbreak, according to Navy officials.

An unspecified number of seafarers assigned to the Hawaii-based ship tested positive and isolated the ship, according to Third Fleet spokesman Cmdr. Sean Robertson. Earlier, officials said about a dozen employees had tested positive.

The rest of the crew received tests on Friday in response to the outbreak.

“To maintain the health of the armed forces and maintain operational readiness, most of the crew assigned to the USS Chafee have been placed in restriction-of-movement (ROM) status at hotels in the San Diego area,” said Robertson. “A caretaker crew will remain on board to support the operational readiness of the ship and equipment and to carry out the necessary support functions.”

The ship is being cleaned too, he said.

None of the infected sailors went to the hospital, Robertson said.

The ship was in San Diego for training exercises.