China has placed equipment designed to jam communications on a barren outpost in the South China Sea — a move apparently aimed at bolstering its dominance in a region where it has pushed extensive territorial claims with its maritime neighbors, The Wall Street Journal reports, quoting U.S. officials.

According to the newspaper:

"A U.S. Defense Department official, describing the finding, said: 'China has deployed military jamming equipment to its Spratly Island outposts.'The U.S. assessment is supported by a photo taken last month by the commercial satellite company DigitalGlobe and provided to The Wall Street Journal. It shows a suspected jammer system with its antenna extended on Mischief Reef, one of seven Spratly outcrops where China has built fortified artificial islands since 2014, moving sand onto rocks and reefs and paving them over with concrete."

As The Diplomat, a website that covers the Asia-Pacific region, writes, "It's unclear if the U.S. assessment is backed by other forms of intelligence or imagery alone; the resolution of the commercial imagery is insufficient to definitively substantiate the nature of the equipment, but the U.S. military added an inset showing the kind of equipment it expects has been deployed."

A spokesperson for China's Ministry of Defense declined Tuesday to directly respond to the report, but said the Spratly Islands — which are also claimed by Taiwan, Vietnam, Malaysia and the Philippines — are "Chinese territory."

"China's stationing of troops and deployment of facilities for homeland defense on the islands and reefs is the natural right of a sovereign nation," Senior Col. Ren Guoqiang said. "It is helpful to protecting national sovereignty and security, to keeping maritime lines of communication open and safe, and to safeguarding regional peace and stability."

"It is not aimed at any particular nation. China will resolutely stick to the path of peaceful development and pursue a defensive national defense policy and proactively defensive military strategy," he added.

The electronic jamming equipment would be consistent with a 2016 U.S. Department of Defense report that said China's People's Liberation Army views such electronic warfare as a "force multiplier" and "would likely employ it in support of all combat arms and services during a conflict."

"The PLA's EW units have conducted jamming and anti-jamming operations, testing the military's understanding of EW weapons, equipment, and performance," the report said, according to Defense News.

China sees the South China Sea and its islands and rightful sphere of influence, "dovetailing with its newly reclaimed role of East Asia's dominant power. Also at stake: a strategic waterway with massive oil and gas reserves that potentially could help fuel China's energy-hungry industries and towns," as we have written previously.

NPR's Anthony Kuhn wrote last month that "In recent years, China has reclaimed land on some of the islands and has installed airstrips, hangars and weapons systems, despite Chinese leaders' pledges not to militarize the islands. Vietnam and the Philippines have also built on some contested islands in the area, but to a far lesser extent."

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