Patisserie Valerie shares have been suspended pending an investigation into "significant, and potentially fraudulent, accounting irregularities" and "a potential material mis-statement of the company's accounts".
The company reported the news had "significantly impacted the company's cash position" and "may lead to a material change in its overall financial position".
Patisserie Valerie has requested that its shares be suspended while it conducts a full investigation into its true financial position.
In the meantime, chief financial officer Chris Marsh has been suspended from his role.
Chairman, serial entrepreneur Luke Johnson, said: "We are all deeply concerned about this news and the potential impact on the business. We are determined to understand the full details of what has happened and will communicate these to investors and stakeholders as soon as possible."
The company said it will make further announcements in due course as the results of the investigation become known.
In its half-year report earlier this year, the group reported year-on-year pre-tax profit growth of 14.2% for the six months to 31 March 2018, up from £9.7m the previous year to £11.1m.
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