Yvette Cooper has complained to police after a man on Twitter made death threats to the MP in response to a series of 'Stronger In' emails.
The Labour MP on Tuesday posted a screenshot of the tweet from an account which has now been suspended, and wrote, "got this today for speaking out for Remain... This has to stop."
Cooper, who has been campaigning for a remain vote, received a message on Monday which read: "Hello, Yvette I have received your Stronger In propaganda emails 5 times please stop of I will kill your children and grandchildren."
She later confirmed on Twitter that she had complained to police and Twitter who were now on case. She added: "This is for all of us. Time to stop the hatred."
The incident comes after MPs' expressed concerns for their safety following the murder of MP Jo Cox in her West Yorkshire constituency last Thursday.
Earlier this year Cooper joined other MPs in launching an online public consultation as part of a national campaign against abuse aimed at women on social media.