Following the latest statement from the Hong Kong police, all five missing booksellers associated with the Causeway Bay banned book store are now known to be in police custody in mainland China.

The five co-owners and staff members of Causeway Bay Books and its parent company Mighty Current – which specialises in Chinese political gossip titles – all disappeared late last year. Gui Minhai, a Swedish national, went missing in Thailand last October. During the same month, Lui Por and Lam Wing-kee went missing in Shenzhen, and Cheung Chi-ping went missing in Dongguan. British national Lee Bo disappeared from Hong Kong in December.

What we know so far:

Lee Bo with his wife in China on January 23. Photo: HKFP.

Lee Bo

Gui Minhai. Photo: CCTV screenshot.

Gui Minhai

Owns 34 percent of shares of Mighty Current;

A Swedish national;

Disappeared from Pattaya, Thailand on October 17 with no departure record;

Four Chinese men reportedly entered Gui’s flat on November 3;

His wife received a call from him on November 9 saying he was safe;

Gui’s daughter studying in the UK has reported him missing, and received a message from him via skype on November 13 saying that he has wired her money;

Gui reemerged on Chinese state television on January 17 to confess to a drink driving accident in 2003 on January 17, saying he voluntarily returned to China;

Said to be given a two-year suspended jail term in 2004 and fled overseas that November using fake identification documents;

His age did not match with the drink driving incident suspect;

Swedish police travelled to Thailand to investigate his disappearance.

Lui Por. File Photo: Apple Daily.

Lui Por

Owns 32 percent of shares of Mighty Current and is the company’s general manager;

Used his computer at the store for the last time on October 14;

Reported to have travelled to Shenzhen to meet his wife and went missing on October 23;

On February 4, it was confirmed he was in China;

Lui is suspected to be involved in a case relating to a person surnamed Gui, and stands accused of being involved in illegal activities on the mainland. Criminal compulsory measures were imposed upon him and he is now under investigation.

Lam Wing-kee. File Photo: Apple Daily.

Lam Wing-kee

Store manager of Causeway Bay Books;

Founded and operated Causeway Bay Books before it was bought by Mighty Current;

Used his computer at the store for the last time on October 23;

No information on whether he left Hong Kong by himself, but Lam was reported to be in Shenzhen before he lost contact;

His wife filed a missing person report to the Hong Kong police on November 5;

He called his wife saying he was safe on November 6 following a media report that day;

Lam was confirmed on February 4 to be in China;

Lam is also is suspected to be involved in a case relating to a person surnamed Gui, and stands accused of being involved in illegal activities on the mainland. Criminal compulsory measures were imposed upon him and he is now under investigation.

Cheung Chi-ping. File Photo: Apple Daily.

Cheung Chi-ping

Business manager of Mighty Current;

Used his computer at the store for the last time on October 22;

Travelled to his wife’s home in Dongguan;

Reported to have been taken away by people armed with guns on October 24;

His brother reportedly said he was safe after he went missing;

He was confirmed on February 4 to be in China;

Like Lam and Lui, Cheung is also is suspected to be involved in a case relating to a person surnamed Gui, and stands accused of being involved in illegal activities on the mainland. Criminal compulsory measures were imposed upon him and he is now under investigation.

Xi Jinping and His Lovers by Xi Nuo. Photo: BBC screenshot.

The five booksellers were rumoured to be been taken away due to a book entitled Xi Jinping and His Lovers, which was set to be published by Mighty Current. The book’s author, Xi Nuo, told the BBC that Gui Minhai decided against publishing it after a visit from a Chinese government agent. The book is now available online.

The Hong Kong, British and Swedish governments, the European Union and the United States have expressed concern over the bookseller mystery.

Causeway Bay Books. Photo: Kris Cheng/HKFP.

Questions which remain unanswered:

Where are the five booksellers held in China?

What is the investigation Lee Bo is assisting in?

How did Lee leave Hong Kong for China without a travel document?

Where in China did Lee meet with his wife?

Why did Lee – or his investigators – make a decision to send letters and video recordings to his wife, local newspaper group Sing Tao and Taiwan’s Central News Agency?

How did Gui Minhai travel to China?

What crime was Lui Por, Lam Wing-kee and Cheung Chi-ping involved in?

See also: Full coverage of the missing bookseller controversy