US rights group NAACP condemned "racist text messages" reported to have been sent to Black Americans across the country after Donald Trump's victory in this week's presidential election.
Black people in states including North Carolina, Virginia, Alabama and Pennsylvania reported receiving messages from an unknown source telling them "to report to a plantation to pick cotton," the group said in a statement.
"The unfortunate reality of electing a President who, historically has embraced, and at times encouraged hate, is unfolding before our eyes," said Derrick Johnson, the head of the civil rights group.
Trump, a right-wing populist whose supporters have used racist rhetoric that he has distanced himself from in the past, was reelected after Tuesday's vote, having made gains with - among others - Black voters.
The origin of the text messages was not immediately clear.
The BBC has reported that the Federal Bureau of Investigation is investigating the messages.
On Thursday, US media reported that Black college students in several states had received the offensive text messages, with some signed as having come from "a Trump supporter".
The Southern Poverty Law Center, a prominent rights group, also condemned the messages.
"The text sent to young Black people, including students at Alabama State University and the University of Alabama, is a public spectacle of hatred and racism that makes a mockery of our civil rights history," said Margaret Huang, the group's chief.
Social media users shared screenshots of the messages.
"You have been selected to be a house slave at Abingdon Plantation," read one purported message. "This is mandatory."
"These people always felt this way, now they feel empowered to speak their mind," Joshua Martin, the social media user who had posted the screenshot, wrote alongside it.
In 2023, the United States witnessed at least 11,447 hate-crime incidents, with more than half of them motivated by ethnicity, according to FBI data.
Since 2020, at least 30.3 per cent of US hate crimes have targeted Black Americans, the data shows.
Between 1525 and 1866, more than 12.5 million Africans were shipped across the Atlantic as part of the slave trade, with millions of them bought and sold as commodities and put to work on plantations and elsewhere on the land that became the United States.