US Defence Secretary Mark Esper announced Tuesday that he had accepted acting Secretary of the US Navy Thomas Modly's resignation, adding that the navy chief "resigned on his own accord." Army Undersecretary Jim McPherson, a retired admiral, will replace Modly as acting Navy secretary, he said.

US President Donald Trump said he had no role in the resignation of Modly, but credited him for trying "to end that problem," referring to the controversy surrounding the firing of an aircraft carrier captain. He also said that Modly's decision was an "unselfish thing to do."

COVID-19 outbreak on carrier

The controversy erupted last week after Modly fired Captain Brett E. Crozier, the commander of the USS Theodore Roosevelt, for writing a widely distributed memo seeking urgent help with a COVID-19 outbreak among the ship's crew. In writing the memo, which was leaked to the media, Modly said the captain exercised "extremely poor judgement."

On Sunday, Modly visited the nuclear-powered carrier docked at a port in Guam and delivered a speech to the crew, saying Crozier was "either too naive or too stupid" to be in charge of an aircraft carrier.

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'Smart and passionate'

Esper, who had initially backed Modly's "tough decision" to fire Crozier, on Monday asked him to apologize for his comment amid backlash from the crew of the ship as well the US Congress.

"I apologize for any confusion this choice of words may have caused,'' Modly said in a written apology. "I also want to apologize directly to Captain Crozier, his family, and the entire crew of the Theodore Roosevelt for any pain my remarks may have caused."

Instead, he said he believes Crozier is "smart and passionate."

"I believe, precisely because he is not naive and stupid, that he sent his alarming email with the intention of getting it into the public domain in an effort to draw public attention to the situation on his ship,'' Modly wrote

Despite the apology, US House Speaker Nancy Pelosi insisted on Modly's removal. "Sadly, Acting Secretary Modly's actions and words demonstrate his failure to prioritize the force protection of our troops," Pelosi said in a statement.

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Hero's sendoff

Crozier also received an emotional sendoff from sailors onboard the Roosevelt, many of whom said the captain put his career on the line to protect his crew.

About 79% of the 4,800 crew on Roosevelt have been tested for coronavirus, and 230 of them were positive, as of Tuesday.

"The Chief of Naval Operations launched an investigation last week regarding the USS Theodore Roosevelt, which is presently underway. Any further action regarding the former commanding officer, Captain Crozier, will wait until that investigation is completed," Esper said.