Ashton-under-Lyne MP and Deputy Leader of the Labour Party Angela Rayner has received a police questionnaire along with Labour leader Sir Keir Starmer.
Durham Constabulary has issued the questionnaire as part of its investigation of alleged Covid rule-breaking.
The story has made national headlines in the past few weeks.
Both have denied breaking any Covid rules but have stated they will resign if they are fined for breaching Covid rules.
The investigations come following claims about a meeting in the run-up to the Hartlepool by-election on May 6 last year, which took place on April 30 at the constituency office of City of Durham MP Mary Foy.
At that time social distancing rules were in place. However, there were exemptions for work purposes with Labour stating it was a work event.
The investigation follows the Partygate scandal embroiling the Prime Minister and Conservative party, with the PM refusing to resign.

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