A High Court registrar has been told of "concerns" that cash from money laundering might have found its way to Blackpool.
The issue was raised in a preliminary hearing in a bitter legal battle between the League One club's owners, the Oyston family, and its president Valeri Belokon, a Latvian millionaire.
Lawyers for the Oystons said it had come to light that Latvia's financial regulator, the Financial and Capital Markets Commission (FKTK), recently imposed a very heavy fine of more than €1 million on Baltic International Bank (BIB), which is owned by Mr Belokon.
The fine was imposed for "repeated violations" of money laundering rules and "transactions that subjected the bank to a significant money laundering risk," said Eric Shannon, representing club owner Owen Oyston and son Karl, the chairman, and their company Segesta Limited.
Belokon's company VB Football Assets is pursuing a claim for "unfair prejudice" against the Oystons and accusing them of stripping the Seasiders of funds.
Shannon told Registrar Sally Barber in a case management session at the Rolls Building in London that an application might have to be made to amend the Oystons' defence in the light of the new information in order to allege that funds put into Blackpool by Belokon "one way or another were the proceeds of crime, or probably the proceeds of crime."
Shannon suggested there should be a stay of the legal proceedings for one month "so that the parties can talk behind the scenes in an atmosphere of calm."
The suggestion was opposed by Fraser Campbell, appearing for Belokon, who said: "They are making wild and extremely serious allegations which we have responded to in a detailed letter setting out precisely the source of the funds involved."
Campbell said a stay was opposed because of the delay it would cause, adding: "We are very keen they should put up or shut up.
"We do not wish to have another month of having wild allegations thrown about before being brought before the court while the respondents sit on information."
Shannon said they were not wild allegations but based on what the Latvia financial regulator had found.
Refusing to order a stay, Registrar Barber told Shannon: "If you are going to take this anywhere you should get on and do it. There is an element of grand-standing."
The hearing covered a number of issues, including an application by the Oystons for the legal proceedings to be transferred to Manchester, which was adjourned.
Belokon and his company VB Football Assets paid £1.8m in July 2006 for 20 percent of the club shares and then caused £2.7m of loans "on highly generous terms" to be advanced to Segesta and the Oystons.
According to VB Football documents before the court, it was envisaged by the parties that the loans would in due course be converted into a further 30% of shares for the company after tax losses had been used by Segesta.
On the understanding that both sides would enjoy an equal quasi-partnership, Belokon made available further substantial sums to buy players.
The result was Blackpool FC was promoted to the Championship and then, in 2010, to the Premier League.
The documents state: "Promotion to the Premier League produced unprecedented revenues for the company, particularly in respect of television rights.
"However, instead of investing those funds in, for example, a strengthened playing squad, or using them to pay dividends to shareholders, the respondents (Segester and the Oystons) caused enormous sums to be transferred to themselves and their associated companies.
"Perhaps the most egregious example was a payment to [83-year-old Owen Oyston's] personal service company of £11m in the 2010-2011 financial year as 'director's emolument.'"
The "cash stripping" undermined the club in footballing terms and it lasted only a single season in the Premier League.
The documents also allege that the relationship between the Oystons and the club's supporters "has become so toxic as to result in match-day violence, libel suits, and a boycott of the club."
Segesta and the Oystons are fighting the claims and deny unfair prejudice.