Recent autopsies confirmed two people in the state of California died from the novel coronavirus one month before what was thought to be the first confirmed fatality from the virus in the U.S.

The two individuals died in their homes Feb. 6 and Feb. 17, weeks before authorities declared the first official death Feb. 29 in Kirkland, Washington.

Tissue samples from the two individuals were sent to the Centers for Disease Control and Prevention (CDC), which confirmed they tested positive for COVID-19, Santa Clara County said in a statement Tuesday.

Read more: US: 2 died from COVID-19 before first known death