The US Homeland Security says it is "particularly" concerned about the threat of white supremacists, warning that they are "exceptionally lethal."
"As secretary, I am concerned about any form of violent extremism," wrote acting Homeland Security Secretary Chad Wolf on Tuesday. "However, I am particularly concerned about white supremacist violent extremists who have been exceptionally lethal in their abhorrent, targeted attacks in recent years."
He further cautioned Americans about the dangers facing what he described as the country's "values."
"This violence, perpetrated by anarchist extremists and detailed in numerous public statements that remain available on the DHS website, significantly threatens the Homeland by undermining officer and public safety -- as well as our values and way of life," wrote Wolf.
This is while US President Donald Trump has expressed tacit support for white supremacists ahead of the 2020 presidential election in a campaign marked by hate and divide.
A report by the Centre for the Study of Hate & Extremism at California State University showed in March that there had been an increase in white supremacist attacks both in the US and around the world in recent years.
“White nationalism has reflected a coarsening of mainstream politics, where debates on national security and immigration have become rabbit holes for the exploitation of fear and bigotry,” read the report.