China has brought back anal swab testing to screen for Covid-19 in a bid to stop the spread of the Omicron variant, just two weeks before the Beijing Winter Olympics begin. 

At least 27 people underwent the controversial anal swab tests at an apartment building in Beijing where a 26-year-old woman had contracted Omicron, the city's first recorded case of the variant, according to Chinese newspaper The Beijing News.

The anal tests involve inserting a sterile cotton swab up to two inches (5cm) into the rectum and rotating it several times. The swab is then removed before being analysed in a lab.

Beijing is in the midst of a strict lockdown and testing regime after the city reported its first local Omicron infection on January 15, and 11 cases have been confirmed in the capital as of Thursday afternoon, the official Xinhua News Agency reported.