Hong Kong’s security chief has warned that booksellers are responsible for ensuring their titles do not violate national security legislation, a day after police raided two independent stores and arrested five people on suspicion of sedition.Secretary for Security Chris Tang Ping-keung also reiterated on Thursday that the government would not compile a list of “banned books”, arguing that doing so would create loopholes where offenders could evade the law by simply changing a title.Tang’s comments came after police searched the bookshop Have a Nice Stay in Prince Edward and the Greenfield Book Store in Mong Kok on Wednesday.Officers seized books and arrested five people for allegedly displaying and selling seditious publications.The arrests followed a referral from the Customs and Excise Department, which had intercepted an overseas shipment of books deemed seditious, according to police.“If you are a bookseller, you have a responsibility to ensure that the books you sell do not endanger national security,” Tang said.