China has reportedly begun deploying Russian S-400 surface-to-air missile defense system, South Korea’s local newspaper Dong-A Ilbo, speculating the country might have deployed the system within the Korea’s radar surveillance range.

However, China has not identified the missile defense system’s exact deployment location, but the report states that S-400 might be stationed anywhere in the Shandong Province, Korean Peninsula, with an aim to check moving of South Korean and U.S. forces in time of emergency in the Korean Peninsula.

Last Friday, Russian media reported that China took delivery of S-400 system including missile control station, radar station and fueling installations. China and Russia signed a contract in 2014 to ship three sets of defense system, and the first system has been deployed this time. TASS reported that China plans to complete deployment of all three systems by 2019.

China’s newspaper Ming Pao reported that, if the S-400 is located in the southern coast of mainland China, such as the Fujian Province, the entire Taiwan falls in the system’s range and China can attack Taiwanese air force. This argument is based on a recent development in China where unification by force is taking a foothold.

In contrast, it has been suggested that China has imported the S-400 in order to destabilize U.S.’s latest fighter and stealth cruise missile. Russia also deployed the S-400 in far eastern areas near North Korean borders such as Vladivostok.

The S-400 system has a maximum range of 400 kilometers and a maximum altitude of 185 kilometers.