Videos and photos from multiple media outlets showed officers wearing vests marked with “Police” seizing boxes from the building housing Have A Nice Stay, a bookshop founded by former journalists. A bookseller was seen being taken away.

A few streets away a similar scene played out, with boxes taken from the building housing Greenfield Book Store, according to a video by online news outlet The Collective.

Police later said they raided two stores in Mong Kok district, without identifying them. They arrested two men and three women on suspicion of breaching the 2024 national security law, according to their statement.

This is the third round of arrests linked to independent bookstores after similar operations in March and June that were widely seen as stifling dissent in the Asian financial hub.

The new police statement said an investigation showed the five people were suspected of displaying seditious materials and selling seditious publications on the premises. The publications’ content includes stirring up hatred against the city’s government, judiciary and law enforcement agencies, it said.

Customs officials referred the case after the discovery of allegedly seditious books in a batch of goods shipped to Hong Kong from overseas, police said, without specifying titles.

The bookstores were closed during usual opening hours on Wednesday. Calls to Greenfield and a founder of Have A Nice Stay were unanswered.

Have A Nice Stay had already announced it would shut down on Aug. 30. In a social media post, it said financial difficulties and an elusive red line were among the factors.

Hong Kong was once known for its freedom of publication and freedom of expression. Some Chinese residents crossed the border to buy books deemed to be too politically sensitive on the mainland.

Lam Wing-kee, the owner of Causeway Bay Books until his death earlier this month, made international headlines in 2016 when he revealed that he was held by Chinese authorities after crossing from Hong Kong to the city of Shenzhen. Four others affiliated with the bookstore in Hong Kong disappeared in late 2015.

Lam’s account shocked many people in the former British colony, which Beijing promised would maintain its Western-style civil liberties for 50 years after its return to China in 1997.

Following political changes after anti-government protests in 2019, independent bookstores have been operating in an even more challenging environment.

Amnesty International’s Asia deputy regional director Sarah Brooks said the use of “sedition” offenses to target bookstores demonstrated how the city’s national security framework “is being weaponized to silence dissenting voices and eradicate spaces for free thought.”

“This year’s escalating attacks on Hong Kong’s independent bookstores hammer home the chilling reality of what the city has become: a place where you can be criminalized simply for what’s on your bookshelf,” she said.

Authorities say the national security laws are crucial for the city’s stability. Hong Kong’s Secretary for Security Chris Tang has said the government would not set up a list of banned books, saying it would be pointless to implement in reality.

In March, police arrested the owner and staff of the independent Book Punch store, reportedly on suspicion of selling seditious publications. They included the biography of former pro-democracy media tycoon Jimmy Lai, who was sentenced to 20 years in prison in his national security case.

In June, Hong Kong police arrested two booksellers on suspicion of selling seditious publications and receiving funds from foreign political organizations.

All were later released on bail.