China says Swedish publisher held under criminal law

China said Tuesday that Swedish book publisher Gui Minhai was in custody under criminal law, brushing aside Stockholms protests after he was seized under the eyes of Swedish diplomats last month.

"Because of the violation of Chinese laws, the relevant Chinese authorities have taken criminal compulsory measures against Gui Minhai," foreign ministry spokesman Geng Shuang told a regular briefing, referring to a form of detention.

Chinese officials have given no public reason for his detention.

Sweden's Foreign Minister Margot Wallstrom on Monday called the seizure a "brutal intervention" that was "in contravention of basic international rules on consular support."

But the Chinese foreign ministry said the two countries have "maintained smooth communication" on the case and rejected Stockholm's criticism as "irresponsible".

"The Swedish side should know the case is serious in nature and some Swedish people have played an irresponsible role in this," Geng said.

"China will never accept the irresponsible remarks made by the Swedish side and we strongly require the Swedish side to refrain from doing the things that will undermine mutual respect and overall picture of the bilateral relations."

Gui was one of five Hong Kong-based booksellers known for publishing gossipy titles about Chinese political leaders who disappeared and resurfaced in mainland China.

Gui vanished in 2015 while on holiday in Thailand.

His daughter Angela Gui, 23, told AFP she fears he may now be put on trial and receive a longer sentence, jeopardising his health.

Doctors in Ningbo where Gui has been living said her father may have the neurological disease ALS -- he had been on his way to Beijing to see a Swedish specialist.