Hong Kong reported two deaths in COVID-19 patients, the first fatalities in the financial hub since September, as a record outbreak overwhelms hospitals and testing resources, providing the biggest challenge to its zero-tolerance approach to the virus since the pandemic began.

Two men in their 70s — one inoculated with two doses of China’s Sinovac Biotech Ltd.’s shot, and the other unvaccinated — died this week, health officials said late Wednesday. Both had chronic illnesses. The deaths came as Hong Kong reports its highest case tallies so far, with more than 980 new infections set to be announced on Thursday, local media reported, after topping over 1,000 earlier in the week.

The outbreak, while small compared with other parts of the world, is putting a health system set up to root out every case and wall off all infection from the community under unprecedented pressure. The city had managed to live for months with no local transmission due to onerous anti-virus measures — including flight bans, up to 21 days of quarantine and mandatory hospital admission — but the arrival of the more-transmissible omicron risks shattering this steadfast push for ”COVID zero," the virus strategy embraced by Beijing.