Ten U.S. sailors are missing after the USS John S. McCain collided with an oil tanker in the Strait of Malacca.

The Associated Press reports that the the McCain, a guided missile destroyer, was headed to Singapore for a routine port visit when the accident took place. The collision was with an oil tanker three times the size of the McCain, according to The Washington Post.

Five other U.S. sailors were reportedly injured in the collision. Four of the sailors were taken to a hospital by a Singaporean Navy helicopter and the fifth injured sailor did not need medical attention, according to NBC News. None of the five had life-threatening injuries.

The Navy has begun search and rescue operations to recover the missing.

ADVERTISEMENT

That search included aircraft and helicopters from the USS America as well as ships from Singapore, Indonesia and Malaysia, according to the AP.

The U.S. Navy said the warship arrived at the Changi Naval Base in Singapore, but suffered flooding after the collision.

"Significant damage to the hull resulted in flooding to nearby compartments, including crew berthing, machinery, and communications rooms. Damage control efforts by the crew halted further flooding," the U.S. 7th Fleet said in a statement, according to Reuters.

The incident is being treated as an accident, a Navy spokesman told NBC News.

President Trump, responding to questions Sunday night about the collision following his return to the White House, said, "That's too bad."

Trump later tweeted that his thoughts and prayers were with the McCain's sailors.

Thoughts & prayers are w/ our @USNavy sailors aboard the #USSJohnSMcCain where search & rescue efforts are underway. https://t.co/DQU0zTRXNU — Donald J. Trump (@realDonaldTrump) August 21, 2017

Sen. John McCain John Sidney McCainMomentum growing among Republicans for Supreme Court vote before Election Day McConnell urges GOP senators to 'keep your powder dry' on Supreme Court vacancy McSally says current Senate should vote on Trump nominee MORE (R-Ariz.) on Sunday also said he was keeping those on the ship in his prayers.

"Cindy & I are keeping America's sailors aboard the USS John S McCain in our prayers tonight - appreciate the work of search & rescue crews," McCain tweeted.

The McCain, commissioned in 1994, is named after McCain's grandfather and father, John S. McCain Sr. and John S. McCain Jr., who both served as U.S. Navy admirals.

It's the second U.S. warship to be involved in a collision in the last two months.

The USS Fitzgerald, a guided-missile destroyer, collided with a container ship in June off the coast of Japan. Seven U.S. sailors were killed in that collision. Three senior U.S. Navy officers were removed from command pending discipline.

Rebecca Savransky and Kyle Balluck contributed to this report, which was last updated on Aug. 21 at 7:19 a.m.