The high-profile entries into Hong Kong's 21-day quarantine facilities have left city authorities red-faced as they prepare to install a new “patriots only” legislature, which is scheduled to hold its first meeting next week.

Hong Kong leader Carrie Lam has ordered a probe into 13 top officials who attended the party, vowing that “appropriate action” will be taken after an investigation is complete.

The 13 officials – including the city's police, immigration and anti-corruption chiefs – were ordered not to work during quarantine, and that days spent in isolation will come out of their holiday allowances.

“Government officials must set an example and uphold discipline, maintain a high level of alertness at all times and avoid participating in high-risk activities,” Lam wrote in a late-night statement.

Those senior officials, as well as 19 legislators, were among about 170 people who attended a Monday night birthday bash for Witman Hung, a member of China's top lawmaking body.

A single preliminary coronavirus case was detected at the party, sparking an initial run of quarantine orders on Thursday for a handful of people deemed to be close contacts.