Students gathered outside the main hub of the US Air Force in South Korea, arguing the US military's presence in Gwangju could complicate Seoul's major chipmaking project planned there.
A group of eight South Korean student protestors were in detention and under investigation on Wednesday after trying to break into a US air base, police and the American military said.
The Korean Progressive University Student Union posted social media images of its Tuesday demonstration outside the Osan Air Base, about 50 kilometres south of Seoul.
Members gathered outside the main hub of the US Air Force in South Korea, arguing the US military's presence in the southern city of Gwangju could complicate Seoul's major chipmaking project planned there.
Eight people were detained on Tuesday after they "attempted to unlawfully enter Osan Air Base through the installation's main gate," a US military statement sent to the AFP news agency said.
The military "transferred them to the Korean National Police, who have assumed custody and are conducting the appropriate investigative procedures," it added.
South Korean police told AFP the students are being held in detention but have refused to speak during questioning.
The student group in a statement on Facebook condemned the US military's "interruption" of a chip cluster project slated for Gwangju.
South Korea has benefitted hugely from the AI boom driving manufacturing profits for its chipmaking firms, particularly SK hynix and Samsung Electronics.
The Gwangju Military Airbase is the site designated for a new 800 trillion won (€485 billion) manufacturing hub for the two companies.
The president's office said last month that Seoul and Washington have begun consultations about relocating the airport, part of which is used by the US military.
Washington stations about 28,500 troops in South Korea to bolter Seoul's defences against military threats from Pyongyang.
The US military presence has long fuelled anti-American sentiment among some, with issues including the exploitation of Korean women who work in camp towns serving US troops.
In 2019, nearly 20 South Korean students, associated with a pro-Pyongyang group, broke into the US ambassador's residence in Seoul.
Four of them were arrested over the apparent protest against Washington's demands that Seoul increase its contributions to the costs of defending the South.