A Conservative activist in Peterborough has been arrested after alleged incidents of postal voting fraud.
The man, who is believed to be a low-ranking member of the Conservative branch in Peterborough, was arrested and has been released on police bail.
Cambridgeshire Police said it was investigating a number of alleged fraudulent postal vote applications.
Police said the inquiry concerned about 150 applications to vote in the local election.
A police spokesman said: "Peterborough City Council and Cambridgeshire Constabulary are working closely to reduce the risk of election fraud being committed and ensure voters have confidence in the electoral system."
The Conservative Party said the man had been suspended.
Chairman of the Conservatives in Peterborough Matthew Dalton: "We take allegations like this very seriously and as a consequence we have suspended the membership of the gentleman in question until the police investigation has been finalised."
A Peterborough City Council spokeswoman said: "We are aware that Peterborough police has made an arrest in connection with allegations of election fraud.
"We have been working closely with the police in the run-up to the elections to minimise the risks of election fraud and ensure people in Peterborough are able to use their vote freely without fear or intimidation.
"However, as there is an ongoing police investigation we cannot comment further at this stage."