Federal and state authorities are working to find the origins of racist text messages sent to Black people across the country threatening them with slavery and telling them they were “selected to pick cotton at the nearest plantation.

The FBI and authorities in several states are investigating racist text messages sent to Black people nationwide this week saying they would be brought to plantations to work as enslaved people and pick cotton.

The FBI and the FCC have weighed in on the messages that multiple Black people across the country received on Wednesday.