(Yicai Global) July 25 -- Auto manufacturer BYD, telecoms giant ZTE, iPhone maker Foxconn, drone manufacturer DJI and other large Chinese tech firms have been ordered to put their Shenzhen factories under so-called ‘closed-loop’ management for one week from yesterday, isolating workers at the plant to keep production lines humming amid a new outbreak of Covid-19.

No workers should leave industrial parks unnecessarily and the entrance of people from outside will be strictly controlled for seven days from July 24, the Shenzhen industry and information technology bureau said as the city logged 21 new cases that day. It is the second time this year that the city is restricting movements due to Covid-19, with the previous shutdown being between March 14 and 20.

The new wave hasn't significantly impacted BYD and the firm is adhering to government Covid-19 safety protocols, said the new energy vehicle and battery giant, which has its headquarters and one factory in the city.

It will be an unwelcome development, though, for the world’s top electric car maker, which has set itself the sales target of 1.2 million cars this year, has been struggling to meet demand in the last two years. BYD has five new plants under construction, which are expected to be up and running before the end of the year, hiking annual production to between three million and 3.5 million units, according to an internal circular.

Foxconn’s industrial park in Shenzhen is operating as normal, staff told Yicai Global. No one can enter or leave the premises without testing negative for Covid-19 in the last 24 hours, the Taiwan-based company added.

Some departments have begun working remotely, ZTE said.

Editors: Shi Yi, Kim Taylor