BEIJING (AP) — China is vowing to prevent foreign powers from interfering in Hong Kong's affairs and carrying out acts of "separatism, subversion, infiltration and sabotage."

The latest broadside against alleged foreign backing of anti-government protesters came Friday from a top-ranking member of China's ceremonial parliament, the National People's Congress.

Shen Chunyao was elaborating on a reference in a Communist Party document that said Beijing would "establish and strengthen a legal system and enforcement mechanism for safeguarding national security" in Hong Kong.

Hong Kong, which has a separate legal system under its own constitution, has tried to enact anti-subversion legislation before, only to meet with formidable public opposition. Shen may have been indicating that Beijing may be preparing to take matters into its own hands by passing an ordinance through the NPC.