Hong Kong leader to raise bookseller's detention with China

Hong Kong bookseller Lam Wing-kee listens to a reporter's question during an interview in Hong Kong, Sunday, June 19, 2016. The Hong Kong bookseller whose disappearance sparked international concern says he was so despondent during his detention by authorities in mainland China that he considered suicide. In an interview Sunday, Lam told The Associated Press that he thought about using his clothes to hang himself but couldn't find a way to do it in the small room where he was kept under constant watch for five months. (AP Photo/Vincent Yu) (The Associated Press)

Hong Kong bookseller Lam Wing-kee reacts during an interview in Hong Kong, Sunday, June 19, 2016. The Hong Kong bookseller whose disappearance sparked international concern says he was so despondent during his detention by authorities in mainland China that he considered suicide. In an interview Sunday, Lam told The Associated Press that he thought about using his clothes to hang himself but couldn't find a way to do it in the small room where he was kept under constant watch for five months. (AP Photo/Vincent Yu) (The Associated Press)

Hong Kong's leader says he'll raise concerns with Beijing over the case of a bookseller secretly detained for months in mainland China.

Chief Executive Leung Chun-ying also said Monday officials would review a notification system that's supposed to alert the Hong Kong government if one of its residents is detained by mainland authorities for illegal activity.

Leung told reporters he "attaches great importance" to the case of Lam Wing-kee, one of five booksellers whose disappearance raised international concern over fears Beijing is eroding Hong Kong's wide autonomy.

The bookseller returned to Hong Kong last week and spoke publicly about his ordeal.

In Leung's first public comments on the case, he said he would write to Beijing to express Hong Kong residents' "high level of concern" over Lam's disappearance.