Having only reopened on Saturday 30 November after a closure of more than four years, the Hong Kong Museum of Art (HKMoA) quickly found itself at the centre of ongoing political protests in the territory at the weekend, forcing it to close almost immediately.

Only a day after the museum reopened to the public, Hong Kong police used tear gas to break up a protest that was taking place close to the museum, prompting concerns that its artworks might be at risk.

The rally in the Tsim Sha Tsui district was supposed to be peaceful and was approved by police in advance. Drawing tens of thousands of protesters, about one hour into the rally, police began firing tear gas into the crowd and announced that those who did not disperse could be arrested.

Ahead of the clash, the museum had already posted a notice that it would close early. It's not clear whether fleeing protesters were able to seek refuge in the museum, nor whether either staff or exhibits were affected by the use of tear gas, which can contaminate ventilation systems, according to Clarisse Yeung, a newly elected councillor who studied fine art at the Chinese University.

"Temperature, humidity and acidity of the air can affect the preservation of the artworks," said Yeung speaking to The Art Newspaper. "The police and government still refuse to publicise the ingredients of the tear gas. We cannot afford the damage of these cultural treasures because of the government's incompetence in resolving a political crisis."

A government spokesman indicated that HKMoA was not affected by tear gas, and that it remained open until 6pm, adding that ventilation systems at the Museum of History and the Science Museum had been cleaned. More than 4,800 visitors attended the HKMoA during its first weekend.

The government-run institution closed in August 2015 for a facelift. Its redevelopment has increased its exhibition space by 40 per cent to around 10,000sq m (32,800sq ft) and increased the number of galleries from seven to 12.

An inaugural programme of 11 exhibitions includes four displays that trace the lineage of Hong Kong art, six that draw upon the museum's vast collection of 17,000 works, including those of traditional Chinese ink paintings and paintings by Wu Guanzhong, and a loan show – A Sense of Place: from Turner to Hockney – from the Tate in the UK.