In another blow to press freedom, Hong Kong’s pro-democracy media outlet Stand News shut down on Wednesday after police raided its office and arrested senior staff in the government crackdown on the city's media, according to a Reuters report.

Police did not identify those arrested but local media reported four former members of the Stand News board were arrested. These include former democratic legislator Margaret Ng, pop singer Denise Ho, Chow Tat-chi and Christine Fang – as well as former chief editor Chung Pui-kuen and acting chief editor Patrick Lam.

Police said 200 officers searched the Stand News office and three men and four women, aged 34-73, were arrested on suspicion of "conspiracy to publish seditious publications".

The police action was condemned by Germany and the U.N. Human Rights Office, which said it was alarmed at the "extremely rapid closing of the civic space and outlets for Hong Kong’s civil society to speak and express themselves freely".

The assets of Stand News, the most prominent pro-democracy publication in Hong Kong have also been frozen. This is the second major setback to the freedom of the press after the national security investigation this year led to the closure of jailed tycoon Jimmy Lai's Apple Daily.

"Stand News is now stopping operations," the publication said on Facebook, adding all employees had been dismissed.

Police chief Steve Li  told journalists Stand News had published news and commentary inciting hatred against authorities.

Li said assets worth HK$61 million ($7.82 million) as well as computers, phones and journalistic materials had been seized, and more arrests could take place.