Brazil's civil aviation authority ANAC has called on Brazilian low-cost carrier Gol to explain a check-in systems failure at Rio de Janeiro's two airports today.
The airline would have to provide an explanation in five days, says the ANAC, which did not provide more details of the failure.
The airline's check-in systems had failed at both Galeao and Santos Dumont airports in the morning, according to the ANAC.
Gol officials were not immediately contactable for comment. News reports quoting the airline say Gol had denied there were any issues with its check-in systems at Santos Dumont, and that only its systems at Galeao had experienced problems.
The ANAC says Gol's response will become part of an ongoing audit that the agency is conducting into check-in systems failures at airlines.