HONG KONG - Two people were arrested on Thursday on suspicion of violating the National Security Law by posting secessionist materials online, police said.

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The suspects — a 23-year-old man and his 49-year-old mother — were also found in possession of a cache of weapons at their home. The weapons included a pistol filled with pepper balls, three air guns, two military knives, and a police baton. They posted the weapons online for sale, police said.

They two are also suspected of possessing arms and ammunition without a license and importing strategic commodities.

Senior Superintendent Steve Li Kwai-wah of the police’s National Security Department told reporters on Friday that the duo published a lot of propaganda on social media platforms, promoting anti-government advocacy, including "Hong Kong independence."

Li said the content was published with the intention of inciting hatred and promoting separatism and secession.

The arrestees have vividly illustrated that they have thrown pungent objects at police during the illegal procession of Sept 6, Li said. They also revealed a plan to attack police with more-powerful weapons, he said.

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