The Police Service of Northern Ireland (PSNI) is investigating allegations that several of its student officers may have cheated during training exams.
Assistant Chief Constable Alan Todd said the inquiry was at an early stage.
He said it “centres around the impropriety of student officers inappropriately sharing examination information between each other”.
The Belfast Telegraph has reported that “more than 50” trainee officers are under investigation for cheating.
The paper said several recruits were not allowed to graduate from the PSNI's training college and were sent back for more training after the allegations were raised by a whistleblower.
Mr Todd's statement said: “Given the scale and thoroughness of the investigation being conducted, and making provisions to ensure the robustness of the examination process, some disruption within the college is possible, however we will be working to ensure this is kept to a minimum”.
He added that it “would be premature to consider what all the outcomes might be”.
The Northern Ireland Policing Board, which holds the PSNI to account, said the matter was of “serious concern”.
In a tweet, the board said it has asked the Chief Constable George Hamilton for a report on the issue and on the actions being taken to address it.