HONG KONG - Hong Kong national security police arrested five people Wednesday in connection with two independent bookstores on suspicion of acts with seditious intent, heightening fears over the "unclear red lines" enforced on the city's freedom of publication.

The arrests of three women and two men, aged 30 to 59, were made after police raided the two shops -- Have A Nice Stay and Greenfield Book Store -- both located in the commercial district of Mong Kok, widely known for its prevalence of indie bookstores, according to local media reports.

Security police alleged in a statement that the stores displayed and sold publications containing seditious content, with such materials believed to have incited "hatred" against the Hong Kong government, the judiciary and law enforcement authorities.

The books were found in a shipment of goods sent from overseas to the city and were later intercepted by Hong Kong customs authorities, the statement added.

Scores of items were reportedly taken away in boxes as evidence from Have A Nice Stay, which on Tuesday said it will shut down on Aug. 30 due to financial hardships and the "unclear red lines" that make it difficult to determine which books can be legally circulated in the semiautonomous Chinese region.

Have A Nice Stay, established in 2022 by former journalists, has sold items including trial records for cases involving pro-democracy activists.

Wednesday's arrests followed crackdowns on several independent bookstores by national security police earlier this year.

In June, Leticia Wong, the founder of Hunter Bookstore and a former pro-democracy district councilor, and her husband were arrested on suspicion of committing acts with seditious intent and money laundering.

In March, security police brought charges against Pong Yat-ming, owner of Book Punch, and three of his staff for knowingly selling seditious publications after copies of a biography featuring pro-democracy activist and former media mogul Jimmy Lai were found at the bookstore.

Lai, 78, who for decades was regarded as a thorn in Beijing's side, was sentenced in February to 20 years in prison for collusion with foreign forces and sedition.

Human rights organization Amnesty International on Wednesday urged Hong Kong authorities to immediately stop criminalizing "the peaceful exercise of human rights," saying the use of "sedition" offenses to target bookstores "demonstrates how Hong Kong's national security framework is being weaponized to silence dissenting voices."

The fresh arrests coincided with the start of a weeklong annual book fair, deemed one of the largest events in the local publishing scene and the lifeblood of many independent bookshops in the city.

Just days ahead of the fair, two independent bookshops -- Elmbook and Luck Win Bookstore -- had their slots abruptly canceled by the government-backed organizer, the Hong Kong Trade Development Council, prompting concerns over censorship of the vendors' political stances.

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