Elon Musk's controversial comments at the Unite the Kingdom rally in London have raised doubts over his fellowship of the Royal Society - the world's most prestigious scientific institution.
Addressing the rally organised by right-wing activist Tommy Robinson, Musk criticised "uncontrolled migration" and said: "Whether you choose violence or not, violence is coming to you. You either fight back or you die."
In response, Sir Adrian Smith, president of the Society, wrote a letter to fellows in which he raised concerns about "resorting to the language of violence" and the threat it posed to the organisation's values.
He said the matter would be discussed at the society's next council meeting.