The commander of a US aircraft carrier that has been hit by a major outbreak of coronavirus has been relieved of command for a loss of judgement, acting Secretary of the Navy Thomas Modly announced on Thursday.

“Today at my direction the commanding officer of the USS Theodore Roosevelt, Captain Brett Crozier, was relieved of command by carrier strike group commander Rear Admiral Stewart Baker,” Modly said.

Earlier this week Modly wrote a memo warning Navy leadership that decisive action was needed to save the lives of the ship’s crew, a defense official tells CNN.

“We are not at war. Sailors do not need to die. If we do not act now, we are failing to properly take care of our most trusted asset — our Sailors,” Capt. Brett Crozier wrote in the memo to the Navy’s Pacific Fleet, three US defense officials confirmed to CNN.

Modly said Crozier was relieved because he went outside the chain of command and sent his memo over an unsecured system adding to the chances it could be leaked .

A US defense official told CNN earlier Thursday that 114 sailors from the USS Theodore Roosevelt have tested positive for the virus.

“Decisive action is required. Removing the majority of personnel from a deployed US nuclear aircraft carrier and isolating them for two weeks may seem like an extraordinary measure,” he wrote in the memo. “This is a necessary risk. It will enable the carrier and air wing to get back underway as quickly as possible while ensuring the health and safety of our Sailors. Keeping over 4,000 young men and women on board the TR is an unnecessary risk and breaks faith with those Sailors entrusted to our care.”

Modly said Wednesday that if it turned out the letter was leaked it “would violate the principles of good order and discipline if — if — if he were responsible for that. But, I don’t know that. The fact that he wrote the letter of — to his chain of command to express his concerns would absolutely not result in any type of retaliation. This is what we want our commanding officers to be able to do.”

CNN previously reported that some of the sailors from the USS Theodore Roosevelt will be quarantined in hotel rooms in Guam as the number of coronavirus cases aboard the carrier continues to increase.

On Wednesday Modly said 1,273 of the ship’s roughly 4,800 crew members have been tested for the virus so far and the Navy was still awaiting the results of some of those tests.

He said about 1,000 sailors have been evacuated from the ship and moved ashore to Guam where the ship is currently in port.

“We already have nearly 1,000 personnel off the ship right now. And in the next couple of days we expect to have 2,700 of them off the ship,” Modly told reporters at the Pentagon.

Some sailors will have to remain on the ship.

The Chief of Naval Operations, Adm. Mike Gilday, said that the ship could not be evacuated in its entirety due to the need to continue to perform essential tasks such as the operation of the aircraft carrier’s nuclear reactor.

He said that about 1,000 sailors would have to remain on the ship to perform, about 500 more than was proposed by Crozier in his recent memo.

“This ship has weapons on it, it has munitions on it, it has expensive aircraft, it has a nuclear power plant. It requires a certain amount of people on that ship to maintain the safety and security of the ship,” Modly said.

The outbreak on the ship is escalating rapidly.

Last week the Pentagon confirmed three sailors on the Roosevelt had tested positive and that number had risen to 25 two days later. That number rose to at least 70 on Tuesday and over 100 on Thursday. On Monday, a US defense official told CNN that a second US aircraft carrier, the USS Ronald Reagan, is also facing a “handful” of positive cases.