The bus was in service at the time.
A bus driver was arrested on suspicion of drink-driving in Cork City yesterday.
Gardaí stopped the bus on the Western Road and carried out the test on the driver, which resulted in a fail.
A man in his early 50s was arrested and brought to Bridewell Garda Station, before being released without charge.
A garda spokesman told the Irish Mirror: "Gardaí on patrol on the Western Road in Cork City stopped a bus and conducted a roadside breath test on the driver which returned with a fail.
"A male in his early 50s was arrested at the scene on suspicion of drink-driving and brought to Bridewell Garda Station.
"He was later released without charge. A file will be prepared for the Director of Public Prosecutions."
A file is being prepared for the DPP.
And a spokesman added that the company would like to apologise to any customers impacted by the incident.
He said: "Bus Éireann can confirm that the driver of the 1148 Route 220 service from Carrigaline to Ballincollig was detained following a roadside check at Victoria Cross on the 01st January 2020.
"The vehicle was in service at the time, all passengers were transferred onto another vehicle with a minimal delay.
"We would like to apologise to any customers impacted."
