The white supremacist who organised the Charlottesville rally called counter-protester Heather Heyer a "fat, disgusting communist" and described her death as "payback" in a tweet he later blamed on "xanax, ambien and booze".

Jason Kessler, 34, gloated over the 32-year-old's alleged murder on social media after she was run over and killed in a shocking attack at the "Unite The Right" event in Virginia on 12 August.

Mr Kessler, who blamed "anti-white hate" for violent clashes between protesters, tweeted: "Heather Heyer was a fat, disgusting Communist. Communists have killed 94 million. Looks like it was payback time."

32-year-old paralegal was killed when a car ploughed into protesters (Go Fund Me / Heather Heyer)

Hundreds gather for Charlottesville vigil

The offensive post also contained a link to a defamatory story about Ms Heyer on the neo-Nazi website The Daily Stormer.

Mr Kessler initially claimed his Twitter account had been hacked after seeing the angry backlash from people across the political spectrum on Friday night, writing: "I was hacked last night. I apologize for the tweet sent out from my account last night."

But the following day, a post on the far-right activist's account appeared to admit he wrote the words, before blaming it on a mixture of alcohol and prescription drugs.

"I sometimes wake up having done strange things I don't remember," he explained, before apologising again for his "heinous" comments.

His remarks sparked outrage and were even condemned by fellow white supremacists including National Policy Institute president Richard Spencer.

Jason Kessler, who blamed "anti-white hate" for violent clashes between protestors, tweeted: "Heather Heyer was a fat, disgusting Communist. Communists have killed 94 million. Looks like it was payback time." (@TheMadDimension Twitter)

"I will no longer associate w/ Jason Kessler; no one should. Heyer's death was deeply saddening. "Payback" is a morally reprehensible idea," tweeted Mr Spencer.

Mr Kessler has since deleted his account and says he has been forced into hiding due to "a crushing amount of stress and death threats" in the wake of the Charlottesville rally.

Hundreds of Ku Klux Klan members and neo-Nazis attended the event he organised to protest against a vote by the city’s government to remove a statue of a Confederate general, Robert E Lee, from a local park.

Violence on the streets of Charlottesville Show all 9 1 /9 Violence on the streets of Charlottesville Violence on the streets of Charlottesville Protesters clash and several are injured White nationalist demonstrators clash with counter demonstrators at the entrance to Lee Park in Charlottesville, Virginia. A state of emergency is declared, August 12 2017 Violence on the streets of Charlottesville Trump supporters at the protest A white nationalist demonstrator walks into Lee Park in Charlottesville, Va., Saturday, Aug. 12, 2017. Hundreds of people chanted, threw punches, hurled water bottles and unleashed chemical sprays on each other Saturday after violence erupted at a white nationalist rally in Virginia. AP Photo Violence on the streets of Charlottesville State police stand ready in riot gear Virginia State Police cordon off an area around the site where a car ran into a group of protesters after a white nationalist rally in Charlottesville, Virginia AP Photo Violence on the streets of Charlottesville Militia armed with assault rifles White nationalists, neo-Nazis and members of the 'alt-right' with body armor and combat weapons evacuate comrades who were pepper sprayed after the 'Unite the Right' rally was declared a unlawful gathering by Virginia State Police. Militia members marched through the city earlier in the day, armed with assault rifles. Getty Images Violence on the streets of Charlottesville Statue of Confederate General Robert E Lee The statue of Confederate General Robert E. Lee stands behind a crowd of hundreds of white nationalists, neo-Nazis and members of the 'alt-right' during the 'Unite the Right' rally 12 August 2017 in Charlottesville, Virginia. They are protesting the removal of the statue from Emancipation Park in the city. Getty Images Violence on the streets of Charlottesville Racial tensions sparked the violence White nationalists, neo-Nazis and members of the 'alt-right' exchange insults with counter-protesters as they attempt to guard the entrance to Lee Park during the 'Unite the Right' rally Getty Violence on the streets of Charlottesville A car plows through protesters A vehicle drives into a group of protesters demonstrating against a white nationalist rally in Charlottesville, Virginia. The incident resulted in multiple injuries, some life-threatening, and one death. AP Photo Violence on the streets of Charlottesville Rescue personnel help injured people after a car ran into a large group of protesters after an white nationalist rally in Charlottesville, Virginia AP Photo Violence on the streets of Charlottesville President Donald Trump speaks about the ongoing situation in Charlottesville, Virginia from his golf club in Bedminster, New Jersey. He spoke about "loyalty" and "healing wounds" left by decades of racism.

The day was marred by violence which turned deadly when far-right activist James Fields Jr allegedly rammed his Dodge Challenger into a crowd of counter-protesters, killing Ms Heyer and leaving 19 others injured.

Mr Kessler, president of grassroots organisation Unity and Security for America, was unapologetic during a press conference a day after the tragic events.