In a video posted online by the Chinese Supreme People's Procuratorate, apocalyptic images of Syria and Iraq are contrasted with bucolic views of China today.
"The haze of 'domestic and international concerns' has not dispersed from the Chinese sky," the video says.
"Tibet, Xinjiang, Hong Kong and Taiwan separatism, as well as dissident leaders, lawyers who would fight until death and other agents of Western forces are damaging China's internal stability and harmony. Behind all these incidents, we can often catch a glimpse of the dark shadow of the Stars and Stripes."
In a post on Weibo, the Procuratorate urged people to "stay alert for color revolutions" or see "peaceful and stable China" become like Syria or Iraq.
A warning against independence movements in Taiwan and Hong Kong is overlaid on photos of Joshua Wong
-- a leading Hong Kong pro-democracy campaigner and founder of Demosisto -- and Taiwanese President Tsai Ying-wen
In a statement, Wong dismissed the video as laughable, adding that it was full of "false statements" and highlighting the sentencing Tuesday of Chinese human rights lawyer Zhai Yanmin
for plotting to subvert state power.
"(Zhai's sentence) proves the mainland justice system has no credibility," Wong said.
Pro-independence candidates blocked
Beijing's dark warnings come as authorities in Hong Kong barred several pro-independence politicians from standing in the upcoming elections to the Legislative Council, the city's parliament.
Edward Leung of Hong Kong Indigenous, who won 15.4% of the vote in a by-election last year
, was blocked by the Electoral Affairs Commission from running in September's race.
Speaking to reporters, Leung denounced the commission's decision as political censorship, warning that Hong Kong will never have true democracy as long as it is under Chinese control and he called for revolution.
Leung is one of five candidates who have been told they will not be allowed to run, including Chan Ho-tin of the Hong Kong National Party
and Alice Lai Yee-man of the Conservative Party, which advocates for Hong Kong to return to British control as a route to independence.
Both Leung and Lai signed declarations
vowing to uphold the Basic Law, Hong Kong's mini-constitution, as required by the EAC, but were nevertheless barred from running.
Other candidates who have been approved to run have complained of their political leaflets -- the free distribution of which is a right granted to candidates -- being blocked by the EAC.
Ma Ngok, a professor at the Chinese University of Hong Kong, said the EAC's bungling of the registration process could lead to a bump in support for more radical candidates.
"Voters may seek to send a message to Beijing by casting a vote for these groups," he told CNN.
The EAC did not respond to a request for comment.