The Navy has ended its search for a sailor who went missing earlier this week in the South China Sea, a U.S. defense official told Fox News.

The sailor, whose name is being withheld pending next-of-kin notification, was reported missing about 9 a.m. Tuesday from the USS Stethem approximately 140 miles west of Subic Bay in the Philippines.

An official said at the time that the missing officer had checked in aboard the ship a short time before his mysterious disappearance.

The disappearance was first reported by Defense News. An investigation is underway.

“Our thoughts and prayers are with our lost shipmate, their family and the officers and crew of USS Stethem,” Rear Adm. Charles Williams, commander of Task Force 70, said in a statement, according to Stars and Stripes. “I appreciate greatly the dedication and professionalism shown by all who participated in the search efforts.”

Approximately 10,000 square nautical miles of ocean were searched over 79 hours. However, when the sailor was not found after more than three days, the effort was called off at 4 p.m. Friday Japan time.

This is the second time this summer the Navy has carried out a major search-and-rescue operation in the Pacific. In June, a missing sailor on the USS Shiloh was presumed lost at sea. He was found hiding in the ship’s engine room.

The sailor, Petty Officer 3rd Class Peter Mims, was later charged with dereliction of duty.

Fox News' Lucas Tomlinson contributed to this report.