A South Korean man in his twenties was arrested during a crackdown on pro-democracy protesters by police in Hong Kong.

The South Korean national was among close to two dozen protesters arrested Sunday for unlawful assembly. 

He is the first South Korean known to be arrested for participating in the protests, which have gone on for weeks against a controversial extradition bill that could subject Hong Kong nationals to China’s legal system.

The South Korean man is allegedly in Hong Kong on a work visa and apparently visited a protest site after work.

The South Korean consulate in Hong Kong said its official visited the man after he had been detained by police.

South Korea's Foreign Ministry said it would do all it can to support the man, calling on Hong Kong authorities to fairly investigate the case.