Gardai confirmed the incident in a statement.
"On December 19 2020 shortly after 5:30am, Gardaí attended at the scene of a traffic collision involving a car and van. The driver of the car, an off-duty member of An Garda Síochána, was arrested having failed a roadside breath test for alcohol," the statement said.
"He was taken to a Garda Station and later released without charge. The driver of the van was treated for minor injuries at Cork University Hospital. The investigation is ongoing," it added.
Under drink driving laws a person who fails a roadside breath test is brought to a garda station where a further blood or urine test is carried out.