An investigation has been launched into a Suffolk accountancy business after its clients said they have been made to repay tax refunds received through the firm.
Suffolk police has confirmed officers and other agencies are investigating Apostle Accounting Limited in Stowmarket.
A Suffolk police spokesman said the force had received a "large number" of fraud allegations concerning the business, which is based in Marriotts Walk.
But Apostle has denied any wrongdoing and said the blame lies with HM Revenue and Customs (HMRC), which is now pursuing the firm's former clients for money.
The police spokesman said: "Suffolk police has been made aware of a large number of allegations of fraud involving a business in Stowmarket.
"An investigation is now underway, and officers are liaising with HMRC and other agencies.
"Anyone who believes they may have been defrauded should contact Action Fraud in the first instance."
Apostle, which was founded by Zoe Goodchild a decade ago, has come under fire from its former clients in recent weeks as they have been pursued for money from HMRC.
Several clients have told this newspaper they used Apostle to claim a tax refund – some to the tune of thousands of pounds, with the firm taking a 20% cut – only for HMRC to later say they were not entitled to the money.
Dr Dan Poulter, MP for Central Suffolk and North Ipswich, and Ipswich MP Tom Hunt have written to HMRC calling for it to end the payment demands.
Apostle has repeatedly been contacted for comment from this newspaper, but no response has been provided since Sunday afternoon.
A statement provided last Friday said Apostle was taking the matter "extremely seriously" but said the issues clients have faced "showcase an incorrect application by HMRC officers of its own rules/guidance".
HMRC has said it does not comment on individual cases.
Another company, which goes by the name of Apostle Financial Services Limited and lists Mrs Goodchild and her husband Martin as officers, has recently been suspended by the Financial Conduct Authority (FCA).
The FCA said it was unable to comment on the firm's suspension.
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