A group of Hong Kong people, including several young activists, has been intercepted by China Coast Guard while fleeing to Taiwan crossing the border unlawfully.

According to local media reports in Hong Kong, opposition activist Andy Li Yu-hin, who is on bail for breaching the city's National Security Law, was among the suspected stowaways.

Coast guard men from Guangdong intercepted the vessel crossing the border illegally in the waters southeast of Guangdong province around 9 am on Sunday, the China Coast Guard announced on its social media account on Wednesday night.

On Aug 10, Li was arrested together with media tycoon Jimmy Lai and activist Agnes Chow Ting on charges of collusion with foreign or external powers to endanger national security. He also faces money laundering charges for his role in a group that begged foreign powers to sanction Hong Kong. He was released on a HK$200,000 bail and had to surrender his travel documents.