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Political and women's rights activist Dr Shola Mos-Shogbamimu said she would not be silenced after a death threat letter was delivered to her London home.
Dr Mos-Shogbamimu said the twisted threat was posted through her front door telling her she was on a "kill list" and would be "executed" along with her family.
'Violated my home'
"When my daughter picked up the mail and handed it to me I saw a handwritten envelope," she told ITV News London.
"I opened the letter and started to read the contents and my initial reaction was how am I going to protect my family?
"It was clear from the intent from the first line that it was an intent to cause harm or death to myself and my family.
"The contents did not surprise me because I get this a lot online.
"But the fact that whoever these people are found my home and violated the sanctity of my home which was very unsettling," she added.
The sender claimed to be from National Action, a UK-based right-wing extremist terrorist organisation founded in 2013.
The letter began by saying "we are watching you" and continued: "Shola you are a constant troublemaker and liar who appears on television frequently.
"We have placed you on our kill list and intend to kill you, your children and your husband.
"You have gone too far and it is time for you to pay the price. We are looking forward to seeing your blood spill."
The letter goes on to include a string of appalling racist abuse - much of it too graphic to republish.
Dr Mos-Shogbamimu added: "I had to explain this to my children, my 16-year-old and my 13-year-old and ten-year-old and while they are not aware of the attacks I get online of course it was unsettling and shocking for them that a group would be so adamant about ending their mother’s life and threatening their lives as well."
Met Police officers were sent to her home and the counter terrorism unit was also assigned to the high priority case.
A lawyer and academic, Dr Mos-Shogbamimu often comments in the media on women's rights, law, politics, diversity, inequality and exclusion.
The letter said she clearly "belongs in Africa" and suggested she left the UK as soon as possible before she "received her punishment".
"I will not be silenced and I will not be silent, I am not the problem here," she added.
"This country, the United Kingdom, we love so much and the greatness we believe this county has was created, added to and expanded on by people like me.
"We belong here," she said.
In a statement police said: "We are taking this matter seriously and an investigation is under way.
"Due to the nature of the letters and the potential involvement of a proscribed group, the Met's Counter Terrorism Command is leading the investigation.
"We were first made aware of the letters as a result of Twitter posts on Monday, 20 February.
"Officers have contacted the victims to request statements and to offer our full support.
"No arrest has been made at this stage and enquiries continue.
"If you have received a letter, or you have information that could help officers identify the senders of these letters, please call 0800 789 321."
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