Police in Nottingham have confirmed they are investigating an allegation of electoral fraud in a city council ward.
There are claims people may have voted twice
They are studying a claim from the Liberal Democrats, who were defeated by Labour in Berridge Ward by 20 votes, that some people may have voted twice.
The party said it had given evidence to the police and Labour says it is awaiting the outcome of the probe.
A police spokesman confirmed: "An investigation into electoral fraud is under way."
Three Labour candidates - Carole Jones, Mohammed Ibrahim and Hassan Ahmed - were elected to represent Berridge on the authority.
There was a recount in the ward on election night after one Liberal Democrat candidate polled only 20 votes fewer than one of the successful Labour candidates.
Labour retained control of Nottingham City Council following the local elections on 3 May.
Labour gained four seats, bringing their total to 42, from 38.
There was no change for the Conservatives, who held their seven seats, while the Liberal Democrats lost two of their eight seats.
The Independents also lost two seats, leaving them without representation.