Police investigating an allegation of the burning of ballots in the Peterborough by-election have concluded that no offences were committed.
The ruling marks the end of Cambridgeshire Police's fourth investigation into alleged electoral fraud in the June 6 by-election, including one allegation of bribery and two relating to postal votes.
A fifth allegation, of a breach of privacy of the vote, is ongoing.
Labour's Lisa Forbes won the seat, vacated by disgraced former MP Fiona Onasanya, but runners-up the Brexit Party claimed that vote-rigging may have played a role in the victory.
And Brexit Party chairman, Richard Tice, said there had been "rumours" about Ms Forbes's win, including claims of "vote-rigging", and alleged a "convicted electoral fraudster" had acted as an election agent for the Labour Party.
The Labour Party rubbished these claims as a "desperate attempt" to excuse a defeat, describing the allegations as "nonsense".
A spokeswoman defending the party said they had "fully complied" with laws and regulations.
Addressing the claims, she said: "This is nonsense. This person was not an agent for the Labour Party and was not involved in the running of Labour's campaign in any way.
"This is a desperate attempt by the Brexit Party to make excuses for their defeat. Labour won the Peterborough by-election fairly and squarely."