Angela Rayner has been the victim of death threats and a string of “threatening and abusive” messages, it has been alleged.
Police arrested a 52-year-old man on Wednesday morning at an address in Halifax after the Labour MP received several abusive phone calls, emails and letters over recent weeks.
The Telegraph understands that Ms Rayner has also been the subject of death threats.
Greater Manchester Police (GMP) said the man was arrested on suspicion of malicious communications and had since been released on bail pending further enquiries. The force said that his arrest related to abusive phone calls received on 15 October.
A spokesman for Ms Rayner confirmed on Wednesday that the Labour MP for Ashton-under-Lyne, her staff and her family were on the receiving end of a number of "malicious" communications.
"We are working with the police to ensure that the perpetrators of these crimes are brought to justice and Angela would like to thank the police for their work during these investigations," the spokesman added.
"Abuse and threats of this nature don't just have an impact on Angela but also on her family, her children and her staff who are on the receiving end of these communications."
Ms Rayner has cancelled a number of constituency surgeries in recent weeks due to fears over her safety.
In a tweet sent on Wednesday afternoon, she thanked the police for supporting "me, my family and my staff during this time, which has been particularly difficult for my children".
'Bullying behaviour completely unacceptable'
Detective Sergeant Christopher Dean, of GMP's Tameside district, said: "Abusive, threatening or bullying behaviour towards anyone is completely unacceptable and we will always do what we can to ensure those responsible are identified and held accountable for their behaviour.
"Although we have arrested one man our investigation remains very much ongoing and we will continue to pursue all available lines of enquiry to identify all those responsible."
The arrest comes amid increasing concern for politicians safety, after the Conservative MP Sir David Amess was stabbed to death in a constituency meeting in Southend-on-Sea, Essex. Ali Harbi Ali, 25, has been charged with his murder and will go on trial next year.
In 2019, a 23-year-old man from the far-Right group National Action was jailed for life for plotting to murder Ms Rayner’s colleague, Labour MP Rosie Cooper.
Jack Renshaw, 23, from Skelmersdale, Lancashire, was sentenced to at least 20 years in prison after admitting to preparing an act of terrorism and wanting to "replicate" the murder of Jo Cox.
Ms Rayner, 37, recently received criticism for making "Tory scum" remarks at Labour’s party conference. She later defended her comments as being made in the "street language" of her northern working-class roots.
The deputy leader of the Labour Party is a mother of three sons and married her trade unionist husband, Mark Rayner, in 2010, but they have since separated.
In 2019, Ms Rayner, who is also a grandmother, revealed that she had installed panic buttons in her home after receiving rape and murder threats.
The MP said: "It was only a couple of weeks ago someone claiming to be a Jeremy Corbyn supporter was arrested for making threats to rape and murder me on social media. My house has panic buttons fitted."
Ms Rayner is currently on bereavement leave after losing a close loved one and aims to return to work "as soon as possible".
