Two more Boeing employees at its Everett factory have tested positive for COVID-19 over the past 24 hours, bringing the total cases to three at the site.
Everett factory near Seattle in the northwestern state of Washington, one of the areas most affected by the Coronavirus in the US.
Boeing health services confirmed the cases, and said all infected patients will remain in quarantine and receive medical care until they fully recover.
Company has stepped up deep cleaning of the site, specially at high-touch areas, and asked the staff self Quarantine if suspected of being infection.
Boeing Everett factory, where Boeing 747, 767, 777, and 787 are assembled, employees around 30,000 people.