An addition by the People's Liberation Army to the city's harbour light show has divided opinion, with some seeing the neon display on the garrison's Admiralty headquarters as sinister and others describing it as a mere decoration.
The flashing lights installed on the newly renovated building spell "Chinese People's Liberation Army" in giant characters.
Professor Ray Yep Kin-man, of the City University's department of public policy, said the display was meant to emphasise the central government's sovereignty over Hong Kong.
"It is sensitive timing," Yep said, a day after the State Council issued its white paper emphasising Beijing's "comprehensive jurisdiction" over Hong Kong.
"They should know such an installation could touch a nerve with Hongkongers."
Helena Wong Pik-wan of the Democratic Party said the neon lights were "disturbing".
"I think it is threatening, it is telling Hongkongers that 'we are here' … It is not in unity with the buildings nearby and it destroys the entire night view," she said.
But pro-government politician Regina Ip Lau Suk-yee said it was no different from displays on commercial buildings such as the Bank of America tower.
The PLA agreed, saying the lights - which were still on trial - were designed to match the urban landscape. The comments came amid a wave of protests over the white paper and followed a 180,000-strong turnout at Victoria Park last week to commemorate the 25th anniversary of the 1989 Tiananmen Square crackdown.
The central government holds "comprehensive jurisdiction" over Hong Kong and is the source of its autonomy, Beijing said yesterday in an unprecedented white paper intended to set the tone for political debate.
It stressed that while the city could, in the future, choose its leader through universal suffrage, that person had to be loyal to the country.
China's national security and interests were at stake, it added.
While similar views have been made by mainland officials before, the timing and the way the document was released show Beijing is determined to put its foot down over Hong Kong's political development.
The white paper, issued by the State Council, said "many wrong views are currently rife in Hong Kong" and added: "Some people are confused or lopsided in their understanding of the policy [one country, two systems] and the Basic Law."
The paper, released in seven languages through Xinhua, came 10 days before the Occupy Central movement's unofficial "referendum" - to be held from June 20 to 22 - on how the 2017 chief executive election should be carried out.
The PLA's lights were "an obvious gesture to stress [Beijing's] authority in the heart of the city," Yep said.
He stopped short of saying it implied a threat of force against demonstrations such as Occupy Central's planned blockade on the business district, but added: "It does send a message to Hong Kong people that [Beijing's] authority is solemn and clear."
But New People's Party chairwoman Ip said Hong Kong should be proud of the PLA.
"My daughter said she is very impressed," Ip said.
"There is no need to feel threatened … In fact, members of the PLA garrison are much better behaved than their British counterparts."