US President Joe Biden has condemned white supremacy, the media, the internet and politics for spreading racist conspiracy theories as he mourned the killing of 10 African-Americans in Buffalo, New York.
Payton Gendron, an 18-year-old white teenager, is accused of opening fire with a semi-automatic rifle in a predominantly African-American neighbourhood of Buffalo.
Authorities say he carried out an act of "racially motivated violent extremism" on Saturday at the Tops Friendly Market, when he shot 13 people.
Gendron has been jailed without bail on a charge of first-degree murder.
He pleaded not guilty.
"White supremacy is a poison. It's a poison - it really is - running through our body politic," said Biden, who spoke moments after meeting with families of the victims as well as first responders.
"The ideology of white supremacy has no place in America. None."
Investigators have said that they are looking into Gendron's online postings, which include a 180-page manifesto he is believed to have authored that outlines the "Great Replacement" conspiracy theory that white people were intentionally being replaced by minorities through immigration in the United States and elsewhere.
"Hate and fear are being given too much oxygen by those who claim to love America," Biden said, blaming politics and profits.
"Now is the time for the people of all races, from every background to speak up as a majority of America and reject white supremacy," he said.
"What happened here is simple and straightforward: Terrorism, terrorism, domestic terrorism," he said.
Biden, joined by his wife, Jill, and a variety of New York political leaders stopped at a memorial set up under a tree to pay their respects near the supermarket where the gunfire rang out.
The scene in Buffalo was an all-too-familiar one for Biden, who once again took up the role of consoler-in-chief.
He said in his speech that he knew something about what the families of the fallen were going through, an apparent reference to the death of his son Beau Biden.
A White House National Security Council spokesperson on Monday said the administration was implementing a "government-wide national strategy to counter domestic terrorism, which President Biden directed his national security team to develop on his first full day in office, recognising that has evolved into the most urgent terrorism threat the United States faces today".
A top FBI official told Congress in November that the bureau was conducting about 2700 investigations related to domestic violent extremism, and the Department of Justice said in January it was creating a new unit to counter domestic terrorism.
Australian Associated Press
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