The Tory party's shock defeat defeat of Nigel Farage in last year's General Election could be declared void, a judge has declared.

The Folkestone Magistrates district judge threw out a bid by Conservative MP Craig Mackinlay to block Kent police from extending their investigation into whether the party broke election spending limits in their fight to stop the Ukip leader from winning the South Thanet seat last year.

Judge Justin Barron said the case was 'wholly exceptional' and there was a 'very significant public interest in the matter being fully investigated' by Kent Police.

Craig Mackinlay (pictured right) attempted to block Kent Police from being granted an extension to their investigation into whether the Tories breached election laws in their bid to defeat Ukip leader Nigel Farage (pictured left) at last year's General Election in the South Thanet seat

He granted the force an extension to the 12-month statutory limit for investigating potential breaches of the Representation of the People Act in last year's General Election - offences that could carry a maximum one-year jail term, although a fine is the most likely.

However a judge could declare the constituency election be re-run.

A joint investigation by the Daily Mail and Channel 4 News had shown the cost of dozens of hotel rooms used by Tory officials and activists in the South Thanet constituency had not been declared on Mr Mackinlay's spending returns, which was limited to around £15,000.

Instead, the costs were declared on the party's national spending returns.

The Folkestone Magistrates district judge today threw out a bid by Conservative MP Craig Mackinlay (pictured with his wife Kati and their chocolate Labrador) to block Kent police from extending their investigation into whether the party broke election spending limits in their fight to stop the Ukip leader from winning the South Thanet seat last year

The Conservative party focused a significant amount of its resources in the constituency as it was desperate to stop Mr Farage from entering Parliament and won by 2,812 votes.

Delivering his verdict today, Mr Barron said: 'The combination of circumstances before me is wholly exceptional and goes far beyond the usual circumstances that would exist in a typical case where election expenses are being investigated.'

He added: 'The consequences of a conviction would be of a local and national significance with the potential for election results being declared void.'

Timothy Straker QC, representing Kent Police, argued that the allegations that the Tories had breached election spending limits was serious enough to warrant an extension to the normal 12-month deadline for investigating reports of beaches to the Representation of the People Act.

He told the court today: 'We have here a circumstance that is exceptional in an election...we have an allegation of national funds being used - in what some might put it - to buy an election.'

He asked: 'What could be more exceptional than one party defeated by another using national funds contrary to law?'

Each constituency candidate has a legal limit for expenditure and their agent is also legally responsible for signing off election returns.

Tory MP Craig Mackinlay (pictured left alongside comedian and FUKP candidate Al Murray, middle and Ukip leader Nigel Farage, left) won the South Thanet constituency at the 2015 General Election by a 2,812 majority

Local spending limits are not uniform but are often around £15,000. Last week David Cameron publicly conceded for the first time that his party may have 'mis-declared' or 'left out' vital General Election expenses.

However, it is unclear whether it was a calamitous ‘administrative error’ – the party’s excuse – or something more serious.

The Mail and Channel 4 initially revealed how tens of thousands of pounds of hotel accommodation for officials and activists had gone undeclared as local candidate expenditure in three crucial by-elections in 2014 and the Thanet South fight last year.

Since then, our investigations have uncovered a further 29 key marginal constituencies in the General Election in which some £38,000 of accommodation for visiting Tory ‘Battlebus’ activists went undeclared.

Information for constituency parties said the Battlebus ‘had the full financial, organisational and practical support’ of Tory campaign HQ, as well as ‘the personal sponsorship of the party chairman, Grant Shapps… and [chief fundraiser] Lord Feldman’.

Twelve forces have sought or indicated they will seek an extension to the statutory limit, with ten of them already investigating.