A police investigation was under way today into alleged irregularities at a local election vote.
The returning officer for Burnley, Lancashire, said he had "grave concerns" about last Thursday's ballot in the Daneshouse with Stoneyholme ward.
Steve Rumbelow, who is also chief executive of Burnley Council, added he did not believe however that the result was affected.
Labour's Shah Hussain was elected with 1,554 votes, ahead of Liberal Democrat Tahir Nawaz (1,071) and Conservative Philip Nutter (101).
Mr Rumbelow said: "I have grave concerns about irregularities in the local election vote in Daneshouse with Stoneyholme ward and I have decided to raise those concerns with Lancashire Police.
"I have no reason to believe this issue would have affected the outcome of the result."
Supt Steve Pemberton, of Burnley CID, said: "I can confirm that we have launched an investigation following council concerns about one of the ballots.
"The investigation relates to the local elections and to one ward only: the Daneshouse and Stoneyholme ward in Burnley."
Two Liberal Democrat councillors in the same ward were jailed for 18 months in November 2006 after they admitted falsifying postal proxy votes.
Manzur Hussain and Mozaquir Ali defrauded dozens of voters during the June 2004 local government elections.
Hussain gathered signed blank forms by knocking door-to-door and Ali then helped fill in the forms to suggest the voter would be on holiday when the election took place.
The votes were then cast for the Lib Dems by the two men on behalf of the voters who were unaware of their actions.
Preston Crown Court heard the falsified forms did not make a difference to the result in which Ali was declared the winner.