The US Navy's top officer has recommended the reinstatement of the aircraft carrier captain fired for sending an email to commanders pleading for faster action to protect his crew from a coronavirus outbreak, officials familiar with the investigation have said.

Key points: Admiral Mike Gilday, the Chief of Naval Operations, met with the chairman of the Joint Chiefs of Staff and the Defense Secretary

Admiral Mike Gilday, the Chief of Naval Operations, met with the chairman of the Joint Chiefs of Staff and the Defense Secretary An official said Admiral Gilday had delivered a verbal update and the Defense Secretary would read the written report before deciding the next steps

An official said Admiral Gilday had delivered a verbal update and the Defense Secretary would read the written report before deciding the next steps Captain Brett Crozier's crew were so upset about his firing that many stood on the deck and chanted his name as he left the ship

The officials said Admiral Mike Gilday, the Chief of Naval Operations, recommended that Captain Brett Crozier be returned to his ship.

Captain Crozier was abruptly removed earlier this month by acting Navy Secretary Thomas Modly, who resigned days later. His return to the ship would reunite him with crew members so upset about his firing that many crowded together on the deck and applauded and chanted his name as he strode off the ship.

As of Friday, 856 sailors on the USS Theodore Roosevelt have tested positive for the virus and four are hospitalised.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 34 seconds 34 s Sailors gave Captain Brett Crozier a raucous send off after he was relieved over coronavirus letter

One sailor has died and more than 4,200 of the ship's nearly 5,000 crew members have been moved onto Guam for quarantine.

Admiral Gilday met with General Mark Milley, chairman of the Joint Chiefs of Staff, this week and with Defense Secretary Mark Esper to lay out his recommendations.

An official said Mr Esper asked for a delay in any public announcement while he considers the recommendation.

Mr Esper's chief spokesman Jonathan Hoffman had earlier suggested Mr Esper was going into the matter with an open mind, and said "he is generally inclined to support Navy leadership in their decision".

After the news of Admiral Gilday's recommendation broke, Mr Hoffman said Mr Esper got a "verbal update" from the Admiral and wanted to read the written report before meeting with the Navy to "discuss next steps".

While other details of the recommendations were not clear, they are expected to address the broader communications and leadership issues on the ship and within the fleet, including how the ship dealt with the growing outbreak, and how that information travelled through the chain of command.

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There have been ongoing questions about whether Navy leaders took too long to acknowledge the ship's problems and if other commanders share blame for not being responsive to Captain Crozier's concerns.

One senior defence official said the investigation covered a complex timeline of communications that spanned multiple time zones and military commands.

Adam Smith, a Washington state Democrat and chairman of the House Armed Services Committee, also urged Mr Esper to restore Crozier to command.

"While Captain Crozier's actions at the outset of the health crisis aboard the TR were drastic and imperfect, it is clear he only took such steps to protect his crew," Mr Smith said in a statement.

The extraordinary episode has captivated a public already overwhelmed by the pandemic. And it has played out as the military copes with the coronavirus by reducing training, scaling back recruiting and halting troop movements even as it deploys tens of thousands of National Guard and other troops to help civilian agencies deal with virus outbreaks across the country.

As the USS Theodore Roosevelt outbreak continues, a second Navy ship at sea is now also reporting a growing number of infections.

Navy officials said at least 18 crew members on the USS Kidd naval destroyer have tested positive, and one sailor has been evacuated to the US.

The Kidd, with its crew of 350, is off the Pacific coast of Central America, where it has been operating as part of a US counter-drug mission.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 20 minutes 20 m The Virus

AP