Yorkshire have pleaded guilty to a charge of destroying or losing data and documents relating to allegations of racism made against the club.
The ECB confirmed this week that Yorkshire had admitted four charges "including a failure to address systemic use of racist and/or discriminatory language over a prolonged period and a failure to take adequate action in respect of allegations of racist and/or discriminatory behaviour".
The club confirmed the report on Thursday morning ahead of next week's Cricket Discipline Commission (CDC) hearings, where a panel will hear disciplinary proceedings brought by the ECB against Yorkshire and seven ex-players.
"It has been reported in a number of news outlets that, in relation to the Cricket Discipline Commission inquiry, the club has admitted a charge of deletion of data and documents," Yorkshire wrote to members on Thursday.
"The CDC proceedings are ongoing and, as such, we are limited as to what we can say at this time. However, we are writing to reassure members reading these reports to let them know that no personal data relating to members of the club was compromised."
Yorkshire said that following Lord Kamlesh Patel's appointment as chair, "it was discovered that emails and documents, both held electronically by the club and in paper copy, had been irretrievably deleted from both servers and laptops and otherwise destroyed.
"After a thorough independent investigation it was established that the deletion and destruction of documents date from a time period prior to the appointment of Lord Patel and relate to the allegations of racism and the club's response to those allegations. The club is not prepared to conjecture publicly as to why this occurred, who was responsible or the motivation for doing so."
The club said that the Information Commissioner's Office (ICO) and the ECB were "informed of the position". The ICO took no action, while the ECB brought a charge "on the basis that the conduct (deletion/destruction) may be prejudicial to the interests of cricket and/or which may bring the ECB and/or the game of cricket into disrepute".
Yorkshire added: "The club has admitted this charge, as there was no viable defence in these circumstances. We wished to let members know the position at the earliest opportunity we were able to and to allay concerns about the integrity of members' data, which the club believes is secure."