According to The Sunday Times Jack Renshaw, formerly a leader of the British National Party's (BNP) youth group, continued to post on Twitter until his account was suspended last Friday (30 December).
"A good time to come back to Twitter. The Jews will learn that they can ban an organisation but they cannot ban an idea," Renshaw tweeted, using the hashtag #NationalAction on around 15 December.
National Action was labelled a terrorist organisation on 12 December.
In his account bio, Renshaw described himself as a "National Socialist activist & apparent "terrorist"; campaigning for a Europe of free & distinct peoples." He managed to get out nine tweets and gather 54 followers before his account was suspended.
One of the group's slogans – "Death to traitors, freedom for Britain" – was uttered by political assassin Thomas Mair, after he killed MP Jo Cox during the EU referendum campaign in June 2016.
In 2014, Renshaw appeared in a BNP Youth recruitment video talking about "attempts to eradicate the British culture and British identity through the forced assimilation of different cultures and different peoples".
He also posted about his homophobia on Facebook that year when he accused his dog of "licking the penises of other males [sic] dogs".
The Sunday Times reports that Twitter shut down other accounts related to National Action following the ban on the group by the Home Office. But Renshaw's account remained active for two weeks following the ban and after other users reported him.
Twitter told The Sunday Times that it would not comment on individual accounts, but would shut down those that "promote violence against or directly… threaten other people" based on their religion, race, or ethnicity.