Trailers carrying US THAAD missile defence equipment entered the deployment site at a golf course in South Korea early on Wednesday, Yonhap news agency reported.
Arrival of the six trailers sparked clashes between locals and police, the agency said. The Terminal High Altitude Area Defense (THAAD) battery is being deployed to counter the threat from North Korean missiles but is strongly opposed by China, which fears it will undermine its own military capabilities.