On Saturday afternoon, a few dozen Chinese soldiers jogged out of their barracks in triple file line, wearing shorts and matching army green T-shirts. They cheerily joined a group of residents, clearing away road blocks set up by anti-government protesters, using brooms and plastic buckets.

One of the officers of the People’s Liberation Army (PLA), when asked by a local journalist what the group were doing, responded: “We volunteered! Stopping violence and ending chaos is our responsibility.” He shouted: “We are spreading positive energy!”

Some of the soldiers wore shirts that said they belonged to “special forces” as well as the “Xuefeng special operations brigade,” both units for counter-terrorism and special operations.

For many in Hong Kong, the message was not a positive one. Pro-democracy activists interpreted it as an attempt to intervene in the city’s affairs. Amid Hong Kong’s quickly escalating political crisis, anti-government protests that are now in their sixth month, many interpreted it as an ominous warning.

“The Hong Kong garrison is one of the most elite units in the PLA and has very tight discipline. Its soldiers will not be allowed on the streets of HK … unless they were ordered to do so,” said Steve Tsang, a professor of Chinese governance at SOAS University of London.

“The deployment was primarily meant to send a clear and powerful signal to the protestors that the PLA could and would be deployed if the Chinese government should see a need to do so.”

According to Hong Kong’s basic law, the PLA garrison is not meant to intervene but can be called on to help maintain public order if asked by the local government. No request has ever been made.

The state-run Global Times, quoting “a source close to the PLA”, said there was “no need to read too much into the clean-up efforts by the soldiers” or any hint of what the PLA Hong Kong garrison “will or will not do next”.

Others saw it as an attempt to normalise the presence of PLA troops on Hong Kong streets. Saturday marked the second time the Chinese troops have left their barracks in the 22 years since the former British colony was handed over to Chinese control.

While that may have worked with the segment of the population frustrated with the protests, it is not likely to intimidate protesters, according to Tsang.

“It will be seen as provocative to them. For young people who have written wills in the course of the last five months, they will not be deterred by the prospect of PLA being deployed to Hong Kong. Why else did they write up wills?”

Whatever the intended purpose, the episode underlines how differently such publicity efforts like these go over in mainland China versus Hong Kong, another example of the differences between the two places.

David Bandurski of the China Media Project pointed out that contrast in an essay. In another video of the exchange, the energetic officer who spoke of spreading positive energy, grew flummoxed when a reporter asked exactly what positive energy, a term Chinese propaganda officials have recently been promoting, meant.

“I’m not doing interviews!” he said, turning away. Another officer then covered the camera filming the conversation with his hand.