Apple and Tesla stocks have tumbled over growing concerns about delays in their production lines in China.
Apple shares hit their lowest point since June 2021. Tesla's stock has dropped 73% from a record high in November 2021.
Companies have struggled to keep production going in China due to Covid restrictions and weeks of lockdowns.
Now they are facing a staffing crunch as China battles a Covid wave after lifting years of restrictions.
Global investors are being cautious ahead of additional interest rate hikes, a global economic slowdown and the ongoing war in Ukraine.
Apple supplier Foxconn says its revenue in November was down 11% compared with the same month in 2021, following unrest at its Zhangzhou plant known as "iPhone City."
This week, media reports said Tesla's Shanghai manufacturing plant had cut production as Covid infections rose in China. The company declined to comment.
But analysts say the company's sluggish sales are evident in the fact that it has offered discounts to both Chinese and North American customers.
Investors have also raised concerns about Tesla's chief executive Elon Musk, who has repeatedly made controversial headlines. He took over Twitter in October after a drawn-out legal battle and since then, Mr Musk has focused a significant amount of his time on running the social media platform. Some have cited his alleged distraction during this time as another reason for the fall in Tesla's share price.
Last week, Mr Musk tweeted asking users if he should continue as the head of the platform - they voted no, prompting him to announce he would resign from his position once a replacement is found.
Analysts say he now needs to rebuild investors' and board members' confidence.
"Musk is viewed as 'asleep at the wheel' from a leadership perspective for Tesla at the time investors need a CEO to navigate this Category 5 storm," wrote Webush tech analyst Dan Ives in his newsletter.
"Instead Musk is laser-focused on Twitter which has been an ongoing nightmare that never ends for investors."
