Kent Police has been asked to investigate claims the Conservatives spent more than they were permitted to in the Rochester and Strood by-election.

Chris Irvine, who acted as the election agent for candidate Mark Reckless, has referred allegations concerning the expenses of the Conservative party to the police.

Mr Reckless triggered the by-election when he defected to Ukip.

The allegations centre on hotel expenses run up by the Conservatives during the hotly-contested by-election in November 2014 that it is said were not properly reported in returns to the Electoral Commission.

The claims were made by Channel 4 News, which alleged the Conservatives may have spent over the £100,000 threshold if a number of hotel expenses during the by-election campaign had been declared.

In a letter to Kent crime commissioner Ann Barnes, Mr Irvine says: “The level of alleged overspend is such that I feel compelled to request that you consider whether it is appropriate for Kent Police to investigate further whether or not the law relating to election spending in a by-election has been breached as alleged in the Channel 4 investigation.”

Channel 4 said that close to £57,000 was spent on hotels in Rochester during the campaign period which were not incorporated in the party’s returns.

Had the party done so, it would have taken them £53,659.83 over the £100,000 spending limit during what is called the regulated period.

In the case of Rochester and Strood, the party filed returns for £96,793.08.

Rochester and Strood Conservative party chairman Andrew Mackness said: “The election expenses were in line with what is permitted in the limits and they were properly declared to the Electoral Commission.”

It is not clear whether the police will be able to carry out an investigation into the claims as any complaint should normally have to be made within 12 months of a by-election.

The by-election in November 2014 was bitterly contested by the parties and the Prime Minister David Cameron made five visits to campaign in support of candidate Kelly Tolhurst.

Hundreds of party activists were sent down to help during the campaign as the party fought to stop Ukip claiming victory.

Meanwhile, related allegations concerning the election campaign in South Thanet, could also be the subject of a police investigation.

Ukip leader Nigel Farage said he expected there would be a similar complaint after Channel 4 reported claims that the election expenses of the Conservatives during the campaign for South Thanet may have breached permitted limits.

These allegations - which have been denied by the party - centred partly on £14,000 spent by the party at a Ramsgate hotel which the party attributed to national campaign expenses, meaning the expenditure did not have to be declared as part of the constituency expenses.

Mr Farage told Channel 4 he did not intend to make a formal complaint himself and neither would Ukip but others might.

"I would be very surprised if a member of the public didn't make a complaint.”