HONG KONG (AFP) - China has confirmed that a missing Hong Kong-based bookseller, one of five men whose disappearance fuelled fears of an erosion of the city's freedoms, is in China's mainland, the city's government said.

Mr Lee Bo, who works for a publishing house that sells books critical of Beijing, was last seen at a book warehouse in Hong Kong on Dec 30 last year.

He was the fifth employee of the Mighty Current publishing house to go missing in recent months.

Three were in China when they vanished, but the disappearance of Mr Lee from Hong Kong and of another man from Thailand has raised fears of the Chinese authorities operating internationally.

A Hong Kong government spokesman said on Tuesday (Jan 19) that the police had received information from the Chinese authorities that Mr Lee was in China.

The spokesman said the letter was issued by the public security department of Guangdong province which borders Hong Kong, but it did not specify where the missing man was.

Hong Kong police have written to the Guangdong security department asking to meet Mr Lee.

Hong Kong's Chief Executive Leung Chun Ying, who has been lambasted in the city for what critics say has been a weak response to the crisis, said Tuesday the government was seeking a meeting with Mr Lee.

"Hopefully we will know more about the case of Mr Lee," he told reporters.

The news will add to fears of pro-democracy lawmakers, activists and some residents who believe the mainland authorities are kidnapping critics to try to silence dissent.

On Sunday, Mr Lee's associate Gui Minhai, who disappeared in Thailand, appeared on Chinese state television.

A weeping Mr Gui said he had returned to China to "take legal responsibilities" for killing a college student in a car accident 11 years ago.

Rights campaigners dismissed Mr Gui's apparent confession, calling it a "smokescreen" to play down concerns that he was being detained by the mainland authorities for his work.

Hong Kong was returned to Chinese rule in 1997 after 150 years as a British colony. Under a "One country, two systems" agreement, the semi-autonomous city is guaranteed freedoms that are not available on the mainland.

However campaigns for greater democracy have been stymied and many activists fear Beijing is imposing its authoritarian stamp on the freewheeling city.