Two former Cathay Pacific Airways Ltd. flight attendants were arrested for violating pandemic rules, Hong Kong police said late Monday, after they were identified as the source of the city’s omicron outbreak. 

The two ex-staffers were charged under Hong Kong’s Prevention and Control of Disease Regulation and are due to appear in court Feb. 9. Until then, they’ve been released on bail. 

Omicron’s emergence in the city, which had avoided a local outbreak of the delta strain, led to an intensification of its zero-tolerance approach to the virus, with travelers from certain countries sent to isolation camps and close contacts of those exposed automatically quarantined. The government has been quick to lay blame at the feet of Cathay, which has struggled under the territory’s shifting quarantine regulations and strict border restrictions, amid a plunge in passenger and cargo traffic. 

Chairman Patrick Healy said last week the carrier would cooperate with investigations into whether crew failed to comply with self-isolation rules and the airline’s practice of rostering crew onto cargo-only passenger aircraft, which allowed them to avoid longer quarantine periods. 

The two attendants arrived in Hong Kong from the U.S. in late December and undertook banned activities while under medical surveillance, police said late Monday. They subsequently tested positive for omicron. If convicted, the pair face a fine of HK$5,000 ($642) and six months in jail. 

Hong Kong’s adherence to the so-called Covid-Zero strategy of trying to wipe out all virus cases has left it increasingly isolated, as other parts of the world start to live alongside Covid and shun harsh curbs like mandatory quarantines and lockdowns. The government is focused on reopening the border with mainland China, the last significant Covid-Zero holdout after countries like Singapore and Australia pivoted to viewing the virus as endemic.