The information is confirmed by FBI Chief Kash Patel.
"This is domestic terrorism. Those responsible will be hunted, arrested, and brought to justice", he writes in a post on X.
The message came just hours after several firebombs were found at a Tesla dealership in Austin, Texas, where the car manufacturer, with Elon Musk as major owner and CEO, has its headquarters.
The incident is the latest in a series of attacks on dealerships and charging stations in several locations in the USA. The attacks are linked, according to several American media outlets, to Elon Musk's support for the USA's President Donald Trump.
Trump and the USA's Justice Minister Pam Bondi have, like Kash Patel, called the attacks "domestic terrorism". Three people have so far been arrested for arson attacks in different states and risk up to 20 years in prison.