By Reuters  April 11, 2018 | 09:38 am GMT+7 China’s territorial claims in the East Sea overlap with those of Brunei, Malaysia, the Philippines, Taiwan and Vietnam. China has installed military jamming equipment on two of its Spratly Islands outposts that can disrupt communications and radar systems, U.S. officials say. Satellite imagery taken by commercial satellite company DigitalGlobe shows a suspected jammer system with its antenna extended on Mischief Reef, one of China’s seven artificial islands, the Wall Street Journal reported. Three of its man-made outposts Fiery Cross, Mischief Reef and Subi Reef now have 10,000-foot runways, airplane hangars, ammunition depots, barracks and deep-water piers for ships. The new jamming equipment was installed within the last 90 days on Fiery Cross and Mischief Reef, according to U.S. intelligence, the Wall Street Journal reported. China claims sovereignty over all of the South China Sea, which is known as the East Sea in Vietnam. Its territorial claims overlap with those of Brunei, Malaysia, the Philippines, Taiwan and Vietnam.