track missiles launched from China" not from North Korea. Chinese experts report that China is focused on the positioning of another THAAD radar system, this one on the Korean peninsula, for gleaning details about China's nuclear weapons delivery systems, such as THAAD's ability to distinguish which missiles might be carrying decoy warheads. Bruce W. Bennett pointed out that China has deployed an S-400 missile system to the Shandong peninsula, between Pyongyang and Beijing, which appears to be a defense against North Korean missiles. In July 2016, American and South Korean military officials agreed to deploy the THAAD missile defense system in the country to counter North Korea's growing threats and use of ballistic missile and nuclear tests; each THAAD unit consists of six truck-mounted launchers, 48 interceptors, a fire control and communications unit, and an AN/TPY-2 radar. Seongju County in North Gyeongsang Province was chosen as a THAAD site, partly because it is out of range of North Korean rocket artillery along the DMZ. This sparked protests from Seongju County residents, who feared that radiation emitted by the AN/TPY-2 radar would impact their health, and damage the region's famed oriental melon crop. On 30 September 2016, the U.S. and South Korea announced that THAAD would be relocated to Lotte Skyhill Seongju Country Club, farther from the town's main residential areas and higher in elevation, to alleviate concerns. On 6 March 2017, two THAAD launcher trucks arrived by air transport at Osan Air Base South Korea, for a deployment. Earlier that day, North Korea had launched 4 missiles. A Reuters article stated that with the THAAD defense system, a North Korean missile barrage would still pose a threat to South Korea, while an article in the International Journal of Space Politics & Policy said that South Korean forces already possess Patriot systems for point defense and Aegis destroyers capable of stopping ballistic missiles that may come from the north, in a three-layer antimissile defense for South Korea. On 16 March 2017, a THAAD radar arrived in South Korea. The THAAD system is kept at Osan Air Base until the site where the system is due to be deployed is prepared, with an expected ready date of June 2017. Osan Air Base has blast-hardened command posts with 3 levels of blast doors. By 25 April 2017, six trailers carrying the THAAD radar, interceptor launchers, communications, and support equipment entered the Seongju site.