The Italian airport of Bergamo Orio-al-Serio, a Ryanair hub for flights to Milan, halted flights on Saturday evening due to technical issues with the landing guidance system and poor visibility, leaving thousands stranded overnight.
SACBO, the company that operates the airport, said in a statement the technical problem was solved around midnight, but a warning on the airport's website said "flights may be delayed or cancelled".
The incident led to the cancellation of 26 departing flights with six diverted to other airports and seven rescheduled for Sunday, local media said.
Thousands spent the night at the airport, with images showing people sleeping on the floor and baggage check-in belts.
The Bergamo online edition of Corriere della Sera daily said the first flights were halted at around 1700 GMT on Saturday.
Real time information about flights on the airport's website showed a long list of mostly Ryanair flights delayed, though several had departed on Sunday morning.
A 0605 GMT Ryanair flight to Cagliari delayed to 0850 GMT was showing as 'departed' as was a 0620 GMT Neos flight to Sharm-el-Sheikh which had been delayed to 0855 GMT.

US, German scientists win Nobel medicine prize for work on light and brain
Nigeria military aircraft crashes with 32 aboard
At least 22 dead after boats collide on Congo river
Spanish PM Sanchez calls snap election for November 29
Hundreds of French schools stay closed ahead of nationwide day of student protests