Giving residents just a few hours’ notice, authorities in China have declared a strict lockdown in the city of Xi’an, confining almost 13 million people to their homes after 127 COVID infections were diagnosed in recent days.

The announcement was made late on Wednesday, setting off a round of panic buying in the city ahead of the midnight deadline. During the lockdown – whose length has yet to be determined – only one person per household will be allowed out of the house once every two days, in order to purchase essentials only. Stores selling non-essential goods have closed. Travel in and out of the city is banned unless a special permit is obtained. Such a stringent lockdown has not been seen in China since the early days of the pandemic in 2020.

Chinese health authorities have not reported which variant of the coronavirus they believe to be responsible for this most recent outbreak, which has been detected in 14 districts in the city of Xi’an but also in five other regions, believed to be linked to Xi’an’s outbreak. One of the affected regions is Beijing, which is due to host the Winter Olympics in just a few weeks’ time.

China is one of just a few countries in the world which claims to be pursuing a “zero-COVID” policy, using methods such as strict travel restrictions, mass mandatory testing, and compulsory quarantine for close contacts with confirmed COVID carriers.