BEIJING (Reuters) - A Chinese military aircraft has landed at a new airport on an island China has built in the disputed South China Sea, state media said on Monday, in the first public report on a move that raises the prospect of China basing warplanes there.

Chinese dredging vessels are purportedly seen in the waters around Fiery Cross Reef in the disputed Spratly Islands in the South China Sea in this still image from video taken by a P-8A Poseidon surveillance aircraft provided by the United States Navy May 21, 2015. REUTERS/U.S. Navy/Handout via Reuters

The United States has criticized China’s construction of artificial islands in the South China Sea and worries that it plans to use them for military purposes, even though China says it has no hostile intent.

The runway on the Fiery Cross Reef is 3,000 meters (10,000 feet) long and is one of three China has been building for more than a year by dredging sand up onto reefs and atolls in the Spratly archipelago.

Civilian flights began test runs there in January.

In a front-page story, the official People’s Liberation Army Daily said a military aircraft on patrol over the South China Sea on Sunday received an emergency call to land at Fiery Cross Reef to evacuate three seriously ill workers.

They were then taken in the transport aircraft back to Hainan island for treatment, it said, showing a picture of the aircraft on the ground in Hainan.

It was the first time China’s military had publicly admitted landing an aircraft on Fiery Cross Reef, the influential Global Times tabloid said.

It cited an military expert as saying the flight showed the airfield was up to military standards and could see fighter jets based there in the event of war.

Chinese Foreign Ministry spokesman Lu Kang said such rescue missions were part of the military’s “fine tradition” and that it was “not at all surprising” they had done this on China’s own territory.

The runways would be long enough to handle long-range bombers and transport aircraft as well as China’s best jet fighters, giving it a presence deep in the maritime heart of Southeast Asia that it has lacked until now.

More than $5 trillion of world trade is shipped through the South China Sea every year. Besides China’s territorial claims in the area, Vietnam, Malaysia, Brunei, the Philippines and Taiwan have rival claims.