WASHINGTON -- The long-awaited U.S. Army-owned Terminal High Altitude Area Defense system has started to arrive on the Korean peninsula in pieces.

The "first elements" of the THAAD system have landed in South Korea at Yongsan Garrison in order to "solely" defend against North Korean missiles, according to a statement from U.S. Pacific Command issued late Monday night.

The statement took pains to note THAAD is "strictly a defensive system" in the wake of China's opposition to the THAAD deployment in South Korea.

The U.S. and South Korea decided officially in July last year to deploy the THAAD system to the country as North Korea continues to conduct intermediate-range ballistic missile launches. These tests are growing in number and complexity.

The two countries had been conducting informal discussions for years on whether to deploy the system but entered into formal discussions in February 2016.

The battery will be operated by U.S. Forces Korea.

Each THAAD unit consists of six truck-mounted launchers, 49 interceptors, a fire-control and communications unit, and an AN/TPY-2 radar.

The first THAAD battery — and currently the only deployed system — was set up expediently in Guam several years ago to protect U.S. forces and allies in response to North Korean aggression. That battery appears to be there for the long haul.