MP's party received payment from Northampton Town developer

David Mackintosh became the Conservative MP for Northampton South in May 2015

A Conservative MP's local party was given undeclared payments linked to a businessman involved in a stalled stadium development, it has emerged.

David Mackintosh's party received a £6,195 payment for tickets from Howard Grossman, the director of a company overseeing work at Northampton Town FC.

Mr Mackintosh was leader of the borough council when it approved a £10.25m loan for the plans. Millions of pounds of the money is currently unaccounted for.

He declined to comment on the payments.

Three individuals with links to Mr Grossman also paid £10,000 into Mr Mackintosh's general election fighting fund, a BBC investigation found.

The payment to Mr Mackintosh's party from Mr Grossman and one of the donations for £10,000 were not declared to the Electoral Commission.

'Unaccounted for'

Failure to declare donations could, dependant on the circumstances, result in a fine or even be a criminal offence.

The £10.25m was loaned for the development of Sixfields stadium

A Conservative Party spokesman said: "We are looking into the matter."

Mr Grossman was director of 1st Land, the company set up to oversee the rebuild of the League Two club's Sixfields stadium. It subsequently went into administration.

Efforts are now being made to trace the £10.25m loan. Work on the stadium remains incomplete and the main contractor is owed £2m.

Mr Mackintosh, who was elected as Northampton South MP in May, oversaw the authority's role in the Sixfields project and the unsecured loan.

The BBC has examined the close links between Mr Mackintosh and Howard Grossman, owner of the County Group, at the time planning permission was granted.

Two years ago Mr Mackintosh attended a celebrity ball at the Dorchester Hotel in London paid for by the County Group. It was six days before a crucial planning meeting, although Mr Mackintosh himself was not on the planning committee.

His £500 ticket for the Amy Winehouse Foundation fundraiser, attended by stars such as Pixie Lott, Barbara Windsor and Jerry Hall, is not recorded in his borough council declaration of gifts and hospitality.

However, it is included in Mr Mackintosh's declaration as a Northamptonshire county councillor.

Mr Mackintosh attended a celebrity ball at the Dorchester Hotel in London, paid for by the County Group, attended by singer Pixie Lott

Mr Grossman was involved in a general election fundraising event for Mr Mackintosh last November at the prestigious Conservative Carlton Club in London.

The £295-a-head gathering was organised by Northampton Conservatives, but several personal invitations were sent out by the businessman, telling a Sixfields contractor it was a "great opportunity for meeting and be involved with nhampton (Northampton) council".

Timeline of a £10.25m council loan

September 2013: Northampton Borough Council agrees to loan League Two Northampton Town £10.25m towards the redevelopment

May 2015: Former leader of the council David Mackintosh elected MP for Northampton South

October 2015: Northampton Town are issued with a winding-up petition by HM Revenue and Customs

November 2015: Police start full-scale investigation into "alleged financial irregularities" involved in the loan to the football club, while it is announced a takeover deal at Northampton Town may stop it going into administration.

Mr Grossman subsequently sent £6,195 to Northampton South Conservative Association.

The following month, Northampton Borough Council approved outline planning permission for the land adjacent to Sixfields.

The BBC has looked at the accounts of Northampton South Conservative Association. Between May and June last year, three payments of £10,000 each were made from the following:

1. Al Mayfield, a DJ and hypnotherapist and Grossman family friend. He was also on the organising committee of the Amy Winehouse Foundation fundraising event. Mr Mayfield did not respond to BBC calls.

2. Gary Robert Platt. Documents filed at Companies House show Mr Platt was a director of a firm which lists two employees of Mr Grossman's County Group as co-directors. The BBC has been unable to contact Mr Platt.

3. In relation to Leonard Western. Mr Western is also linked to Howard Grossman and the County Group. The BBC has been unable to contact Mr Western.

It is perfectly legal and normal for business people to give money to political campaigns but there are rules about declaring those payments.

Suresh Patel, the chairman of Northampton South Conservatives and the MP's election agent, went to the Conservative Party chairman Lord Feldman last week. He gave him a dossier detailing his concerns about the links between Mr Mackintosh and Mr Grossman, and for the first time admitted that the £10,000 from Mr Platt had not been declared. The receipt from Mr Grossman was not specifically discussed.

Northampton council leader David Mackintosh was named Philistine of the Year by satirical magazine Private Eye over the sale of an Egyptian statue from its museum

Mr Patel confirmed to the BBC that the undeclared payment from Mr Grossman was for tickets to an election fundraising event.

He said the Electoral Commission was not informed of the payment by Mr Platt because of an administrative error. The payments by Mr Mayfield and Mr Western were passed on. Mr Patel has since notified the Commission of the Platt payment.

In a statement via his solicitors, Mr Grossman told the BBC: "Howard Grossman paid £6,195 for tickets to attend an event hosted by Mr Mackintosh as part of his election campaign. Mr Grossman is unable to comment on contributions made from other individuals you have mentioned."

By law, personal donations of more than £500 and donations to local associations of more than £1,500 must be declared to the Electoral Commission.