The Japan-based 7th fleet says that search and rescue operation has now been launched from the carrier.
Eight people have been rescued and are in "good condition" after a U.S. Navy transporter plane carrying 11 crew and passengers crashed into the Pacific Ocean off Japan, the U.S. Navy's 7th Fleet said Wednesday.
It said the ship was operating in the Philippines Sea when the crash happened at 2.45 p.m.
"The Maritime Self-Defense Force is now searching with US forces", Japanese Defense Minister Itsunori Onodera said, according to public broadcaster NHK.
The cause of the crash wasn't immediately known.
The USS Ronald Reagan is now operating in the Philippine Sea. Japan's Defence Ministry said the crash site is about 150km northwest of Okinotorishima, a Japanese atoll.
Trump said in a tweet: "We are monitoring the situation".
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Both King and O'Donnell applauded the courage the women must have had to take steps to speak up about what happened to them. The accusers, who ranged in age from 21 to 37 at the time of the alleged encounters, were not employed by CBS or PBS .
White House spokeswoman Lindsay Walters provided no additional details or comment on the incident. "Prayers for all involved".
The names of the crew and passengers on board of the plane are now being withheld.
USS Ronald Reagan is conducting search and rescue operations.
The US Navy lost 10 personnel in August, when the USS John McCain collided with a tanker near Singapore.
Two months earlier in June, the USS Fitzgerald and a cargo ship smashed into each other off Japan, leaving seven sailors dead.
The Navy has concluded that the collisions were avoidable and resulted from widespread failures by the crews and commanders, who didn't quickly recognise and respond to unfolding emergencies.