The Foreign Ministry emphasized on Thursday that a former employee at the British Consulate General in Hong Kong－who had been detained for 15 days by police in Shenzhen, Guangdong province－confessed to all his offenses, and his lawful rights and interests were guaranteed.

The former employee, Simon Cheng Man-kit, was detained for breaking the Public Security Administration Punishment Law, the ministry said. Cheng was detained for soliciting prostitutes, according to a statement by the local police in August.

Ministry spokesman Geng Shuang made the remarks after reports that British Foreign Secretary Dominic Raab summoned Liu Xiaoming, the Chinese ambassador to the United Kingdom, to "express outrage at the brutal and disgraceful treatment" of Cheng during his detention and that he expects "the Chinese authorities to investigate and hold those responsible to account".

The spokesman refuted Raab's remarks, saying that Liu had lodged representations to the UK during his meeting with Raab to express opposition and indignation against their erroneous words and deeds on Hong Kong in recent days.

He quoted Liu as saying that as a Chinese citizen of Hong Kong, Cheng's case is an internal affair for China; that the Chinese public security authority dealt with the case in accordance with the law; and that the so-called representations from the UK are completely unreasonable.

Liu urged the UK to immediately stop any form of interference in Hong Kong affairs, which are China's internal affairs.

Cheng's case drew attention again after he told the BBC in a recent interview that he was tortured in police custody.

The police in Luohu district, which borders Hong Kong, rebuked such claims on Thursday, saying they protected Cheng's lawful rights. The police said that Cheng's case had been dealt with in accordance with the law, and there was no use of torture to coerce his confession.

According to a video released by the police, Cheng stated that he solicited prostitutes three times in a 15-day period at a club in Luohu.

Cheng said in the video that he felt disgraced and ashamed of his behavior and was too embarrassed to tell his girlfriend and family. He said that he felt guilty and blamed himself.