Missing, presumed detained: Hong Kong publishers of books critical of China go missing
Police contacted over disappearance of four executives, including two co-owners of publishing company known for books critical of Chinese authority

Mystery surrounds the whereabouts of four men working for a Hong Kong company publishing books on sensitive mainland issues - amid fears they may have been detained by mainland authorities.
The four include Gui Minhai, a mainland-born Swedish national and co-owner of Mighty Current publishing company, which has published about 80 books on China since its establishment in 2012. The company also runs a book shop in Causeway Bay.
Its books mostly cover mainland politics, power struggles and scandals involving officials.
A colleague and co-owner, surnamed Lee, said Gui's whereabouts were unknown since he went on holiday in Pattaya in Thailand in the middle of last month.
Gui was last heard of when he sent an email on October 15 to printers asking them to get ready for a new book. Since then, Gui could not be reached, Lee said.
