6 December 2016, 13:28 GMT
MOSCOW (Sputnik) — According to the BBC broadcaster, the threats were made online. No more details have been provided.
Miller, an investment manager and philanthropist, challenged the legitimacy of UK decision to leave the European Union, arguing that the the UK government did not have constitutional authority to trigger Article 50 of the Lisbon treaty without the approval from the Parliament.
On June 23, the United Kingdom decided via a referendum to leave the European Union. May stated that the country would trigger Article 50 by the end of March 2017, thus starting withdrawal negotiations.
