China ordered a lockdown of the 9 million residents of the northeastern city of Changchun amid a new spike in COVID-19 cases in the area attributed to the highly contagious omicron variant.

Residents are required to remain at home, with one family member permitted to venture out to buy food and other necessities every two days. All residents must undergo three rounds of mass testing, while non-essential businesses have been closed and transport links suspended.

Chinese officials reported 1,807 new symptomatic COVID cases on Sunday — more than triple the number reported the previous day and the country’s highest figure in two years.

The northeastern province of Jilin accounted for 78 percent of the national total, China’s National Health Commission said. The nationwide total easily topped Saturday’s count, which was already a record for cases since the country’s first outbreak in early 2020 — sparking a fresh round of lockdowns.