Security Secretary Chris Tang says the government will make use of whatever means possible to "correct" Google's search results, after it refused to make sure that March of the Volunteers comes up as Hong Kong's national anthem.

Tang on Monday quoted the internet company as saying it couldn't change the top results on its search engine because they are based on an algorithm, adding that he finds this explanation to be both unacceptable and unbelievable.

Hits on the search engine bring up the name of a song related to the 2019 protests as well as God Save The King, rather than China's anthem. The protest song has been played by mistake at a number of international sporting events in recent weeks.

Tang said the search engine results hurt the feelings of Hong Kong people.

The security chief added that it is public knowledge that once you place ads on Google these come higher up on the results page.

Tang said the SAR government will use whatever means possible to "correct" the problem, without elaborating.

He also told reporters that recent demonstrations in Hong Kong died down partly because he warned they "showed signs of a colour revolution".

Several small-scale, peaceful rallies were held in support of mainland protests against Covid measures, including on university campuses.

Tang said he had a responsibility to remind university management that their campuses can't be used as a base for actions that threaten national security.

"I also have to come out to warn [people] who try to cause social unrest in Hong Kong, you will fail because we'll make every effort to interdict such actions," he said after attending a Fight Crime Committee meeting.

The Secretary for Security said no arrests have been made relating to the Hong Kong protests, but stressed that officers will collect evidence and take any follow up action necessary.