Protesters clashed with police officers in Seongju County of South Korea when U.S. troops started transporting part of a missile defense system to the installation site nearby.

Six trailers were reportedly seen carrying x-band radar, mobile launchers and other elements of the Terminal High Altitude Area Defense system, known as THAAD, entering the site.

This overnight operation came after the U.S. Forces Korea secured the land and amid, what Washington claims, is North Korea’s advancing nuclear and missile threat. THAAD is designed to intercept short, medium and intermediate-range ballistic missiles during their flight. It is believed to be able to intercept missiles coming from North Korea.

Local residents are afraid that after the installation, Seongju will become a priority target for North Korea’s missile attacks. They protested with pickets reading “No THAAD, No War” and “Hey, U.S.! Are you friends or occupying troops?” during the transportation.

Some 8,000 police were dispatched to the scene and had a confrontation with those protesters. At least a dozen people were injured, including the elderly, according to Korea JoongAng Daily.

The system will be operational in the coming days “to better defend South Korea against the growing North Korea threat,” U.S. Pacific Command Chief Adm. Harry Harris told the House Armed Services Committee Wednesday.

South Korea’s Ministry of National Defense also confirmed the installation and expected the test operation of the new system to start early next month, according to South Korea’s Yonhap news agency.

The deployment of THAAD had recently hurt Seoul’s relationship with Beijing, which regards THAAD’s powerful radar as a security and surveillance threat. Chinese Foreign Ministry spokesperson Geng Shuang urged South Korea and the U.S. to withdraw the equipment in his daily briefing Wednesday.

“The deployment goes against efforts made by all parties to settle the issues through discussion and severely sabotage China’s security and strategic interests,” Geng said.

In fear of a potential nuclear war, female activists from more than 40 countries sent an open letter to President Trump demanding a peace deal with North Korea. They said deploying the controversial THAAD missile system in preparation for the war only fueled their fear.

“We are united by our belief that diplomacy is the only way to resolve the nuclear crisis and threat of war now facing the Korean Peninsula,” the letter said. “Peace is the most powerful deterrent of all.”

Telesur