Two United Airlines pilots have been arrested at Glasgow Airport for allegedly failing a breath test before boarding a flight to Newark, New Jersey.
The men, aged 45 and 61, have not been charged but remain in custody and are expected to appear before Paisley Sheriff Court on Tuesday.
Police Scotland confirmed officers were called to the airport at 07:35 BST.
The men were arrested before boarding flight UA162.
It was expected to take off for Newark at about 09:00 but was cancelled.
United Airlines said in a statement the safety of its customers and crew was "always our top priority".
It said: "We hold all of our employees to the highest standards and have a strict, no tolerance policy for alcohol.
"These pilots were immediately removed from service and we are fully cooperating with local authorities.
"At this time, we are working to get our customers back on their journey as soon as possible."
A Police Scotland spokeswoman confirmed two men, aged 61 and 45, have been arrested and remain in police custody pending a scheduled court appearance on Tuesday 6 August for alleged offences under the Railways and Transport Safety Act 2003.
The legislation covers carrying out pilot duties while under the influence of alcohol or drugs.
The limit for alcohol detected in the breath for pilots is less than half the limit for drivers in Scotland.
In 2017, two United Airline pilots were jailed for breaching drink-fly limits at Glasgow Airport.
First Officer Paul Grebenc, 35, was sentenced to 10 months in prison.
His colleague Carlos Roberto Licona, 45, was jailed for 15 months.
Both had been arrested while preparing to take off from Glasgow on 27 August 2016.