US ship sails close to disputed island claimed by China in South China Sea It was the second such operation under the Trump administration

 -- A U.S. Navy destroyer sailed within 12 miles of a disputed island claimed by China in the South China Sea, the second such operation in the past few months.

The USS Stethem, a guided-missile destroyer, on Sunday sailed within 12 miles of Triton Island in the Paracel Island Chain located in the South China Sea, according to a U.S. official.

Triton Island was seized by China from Vietnam in the mid-1970s, and is claimed by China, Taiwan and Vietnam.

The U.S. ship was trailed by a Chinese warship as it sailed near the island, the U.S. official said.

By sailing within 12 miles of the island, the U.S. conducted what is called a Freedom of Navigation Operation. The international standard is that territorial waters extend 12 miles from a shoreline.

The Navy conducts such operations to challenge excessive maritime claims around the world, and Pentagon officials have stressed that they are not directed specifically at China.

On May 24, the USS Dewey destroyer sailed within 12 miles of Mischief Reef, one of seven manmade islands built by China in the Spratly Island Chain, located further south in the South China Sea.

China has extensively developed the artificial islands with airstrips and what appear to be military structures.

New satellite imagery released last week by the Center for Strategic and International Studies' Asia Maritime Transparency Initiative indicates that China is continuing to build military facilities in the Spratly Islands.