HONG KONG: Hong Kong’s security chief said on Thursday that booksellers must ensure the items they sell “do not endanger national security,” a day after authorities arrested five over “seditious” material.

National security police searched two bookshops on Wednesday and arrested five people under suspicion of displaying and selling “items with seditious intent,” the latest in a string of crackdowns on independent bookshops.

AFP reporters saw officers lead a woman in handcuffs to a van and taking away several boxes from Have a Nice Stay, a bookshop run by former journalists.

The city’s security chief Chris Tang told reporters on Thursday: “If you are a bookseller, you have a responsibility to ensure that the books you sell do not endanger national security.”

“I believe booksellers bear this responsibility,” he said, comparing it to food vendors being required to ensure the goods they sell do not “contain poison or breach the law.”