Washington - The US Navy announced a fleet-wide global investigation on Monday after the latest in a series of accidents left another 10 sailors missing and five more injured.
Chief of Naval Operations Admiral John Richardson ordered commanders to set aside time, perhaps "one or two days" within a week, for crews to sit down together after the destroyer USS John McCain collided with a tanker off Singapore.
And this will be carried out in parallel to the start of "comprehensive review" of practices.
"As you know, this is the second collision in three months and the last of a series of incidents in the Pacific theatre," Richardson said.
"This trend demands more forceful action. As such, I have directed an operational pause be taken in all of our fleets around the world."
The admiral did not rule out some kind of outside interference or a cyberattack being behind the collision, but said he did not want to prejudge the inquiry and his broader remarks suggested a focus on "how we do business on the bridge."
US Defence Secretary Jim Mattis, on a visit to Jordan, said Richardson's "broader enquiry will look at all related accidents, incidents at sea, that sort of thing. He is going to look at all factors, not just the immediate one."
Ten US sailors were still missing after Monday's collision between the McCain and the Alnic MC in the busy shipping lanes of the Singapore Strait, near the Strait of Malacca, which left a large hole in the USS John McCain's hull.
It was the second accident involving an American warship since mid-June. A major search involving ships and aircraft from Singapore, Malaysia and the US was launched for the missing sailors.
The badly damaged destroyer limped into port in the southeast Asian city-state of Singapore under escort after the dramatic pre-dawn accident, which sent water flooding into the vessel.
Analysts said the accident, which came after June's collision off Japan involving a US warship, raised questions about whether the US Navy was overstretched in Asia as it seeks to combat Chinese assertiveness in the South China Sea and North Korea's nuclear ambitions.
The US Navy said there was "significant damage to the hull" of the John McCain, which led to flooding of crew sleeping areas, machinery and communications rooms.
"Damage control efforts by the crew halted further flooding," they said in a statement.
A helicopter took four of the injured to a Singapore hospital for treatment, while the fifth did not need further medical attention, the navy said.
The 154-meter vessel could still sail under its own power after the collision with the Liberian-flagged tanker, which was slightly bigger at 600 feet. Two other vessels escorted it into port.
The warship had been heading for a routine stop in Singapore after carrying out a "freedom of navigation operation" in the disputed South China Sea earlier in August around a reef in the Spratly Islands, sparking a furious response from Beijing.
The damaged vessel is named after US Senator John McCain's father and grandfather, who were both admirals in the US navy.
McCain himself, who as a naval pilot was shot down during the Vietnam War and held prisoner, welcomed the review.
"I agree with Admiral Richardson that more forceful action is urgently needed to identify and correct the causes of the recent ship collisions," he said.
"I expect full transparency and accountability from the Navy leaders as they conduct the associated investigations and reviews." .
'Are they doing too much?'
President Donald Trump tweeted: "Thoughts & prayers are w/ our @USNavy sailors aboard the #USSJohnMcCain where search & rescue efforts are underway."
Ridzwan Rahmat, a naval expert at Jane's by IHS Markit, said initial indications suggested the US warship may not have been obeying rules designed to separate maritime traffic passing through the Singapore Strait.
With the accident coming soon after the freedom of navigation operation, he told AFP that it raised questions "whether there is crew fatigue setting in, whether or not the tempo of operations by the US Navy in this region is getting too fast."
"Are they doing too much within this region with North Korea, and Japan and then now in the South China Sea?"
The tanker involved in the collision, which was used for transporting oil and chemicals and weighed over 30,000 gross tonnes, sustained some damage but no crew were injured, and Singapore said there was no oil pollution.
In June, seven American sailors died when the destroyer USS Fitzgerald collided with a Philippine-flagged cargo ship in a busy channel not far from Yokosuka, a gateway to container ports in Tokyo and nearby Yokohama.
The dead sailors, aged 19 to 37, were found by divers in flooded sleeping berths a day after the collision tore a huge gash in the ship's side.
A senior admiral announced last week that the commander of the destroyer and several other officers had been relieved of their duties aboard their ship over the incident.
Both the USS John McCain and USS Fitzgerald are part of the US Seventh Fleet based in Yokosuka.