Protesters shout slogans during a rally near the golf course where the Terminal High Altitude Area Defense (THAAD) system will be deployed in Seongju, South Korea, March 15, 2017. About 200 local residents attended the rally on Wednesday to protest against the deployment of THAAD system. (Xinhua/Liu Yun)

SEOUL, May 1 (Xinhua) -- Protests against the deployment of the U.S. missile defense system continued Monday in South Korea amid rising controversy over which side would pay for the billion-U.S.-dollar costs for the Terminal High Altitude Area Defense (THAAD).

About 150 residents and peace activists blocked the entrance of police buses to a golf course in the southeastern part of the country, where part of the THAAD elements were already installed.

From about 7:30 a.m. local time, a higher-than-usual number of police buses tried to enter the golf course. About 30 buses were carrying some 1,200 policemen, according to photos and documents released by the residents and the activists who have stood sentry right beside the entrance road to the THAAD site.

They blocked the police buses because they saw the reinforcement as a sign that South Korean police could seek again to allow the U.S. forces to move necessary equipment for the THAAD deployment to the golf course.

Two oil tankers, driven by U.S. soldiers, attempted Sunday to enter the golf course, but it ended up in failure as the residents and the activists blocked them.

During the Sunday tussle with policemen, which the residents called the police of the United States, not of South Korea, two were wounded and were taken to a nearby hospital.

Sim Sang-jung of the progressive Justice Party, one of the five major presidential candidates, visited the Soseong-ri village in Seongju county on Sunday to meet and talk with the residents.

During the meeting, Sim said four other candidates should come to the village and watch what was taking place in Seongju, which she described as "war-like situations."

Sim has strongly urged for the reversal of the THAAD deployment.

At about 1:00 p.m. Monday, the residents decided to let the police buses pass the entrance road as it would be a normal replacement of policemen.

In Seoul, three Won Buddhist monks launched an indefinite hunger strike in the Gwanghwamun square just one day after part of the THAAD elements were deployed on April 26.

Their strike would last until the U.S. anti-missile system is completely pulled of out South Korea.

Part of the THAAD elements, including two launchers and a radar, were installed last week following a violent tussle between police and the local residents and the activists.

During the tussle, over 10 people were injured and several others were conducted away.

Controversy emerged about which side would pay the billion-dollar costs for THAAD as U.S. President Donald Trump said last week South Korea should pay the cost for the deployment, which he estimated at 1 billion dollars.

It increased South Korean people's opposition to the THAAD installation as the U.S. missile defense shield would be operated by the U.S. Forces Korea (USFK), not by South Korea's military.

Herbert Raymond McMaster, U.S. national security advisor, said in an interview with Fox News on Sunday that his country would adhere to the deal with South Korea on THAAD "until any renegotiation," indicating a renegotiation on which side would pay the costs.

The South Korean Defense Ministry said Monday that paying the THAAD costs could not become a subject to renegotiations, reiterating that the costs issue was already agreed upon.

Under the Status of Forces Agreement (SOFA), the ministry claimed, the U.S. side bears the burden of the THAAD operation and maintenance, while the South Korean side provides land and infrastructure for the deployment.

Debates were rekindled among major South Korean presidential candidates over the THAAD installation, following Trump's remarks on the payment.

Moon Jae-in of the biggest Minjoo Party, a months-long frontrunner in recent presidential polls, reiterated his position that the final decision on THAAD must be made by the next government.

The country's presidential election is scheduled for May 9 as former President Park Geun-hye was impeached in March over corruption allegations.

Ahn Cheol-soo of the minor centrist People's Party, a runner-up to Moon, said the costs should be paid by the U.S. side.