Shanghai has been plunged into an extended lockdown and some residents face another 10 days of isolation in their homes as China’s strict zero-Covid policy threatens to derail the country’s economy.

The eastern half of China’s biggest city had been due to emerge on Friday from a four-day lockdown aimed at crushing a persistent outbreak of the Omicron variant, but the extension was announced late on Thursday night.

A lockdown of the western half of the city went ahead as planned on Friday morning, leaving a majority of the city’s 26 million people still in lockdown in the latest sign that China’s financial powerhouse is struggling to eliminate the outbreak.