A flight from Brussels to Madrid was delayed by more than two hours while police searched for explosives after a party of Belgian men started making jokes about being Islamists with bombs.
Passengers were evacuated as police conducted their search, officials say.
Prosecutors say the men appeared to be drunk as they were boarding the Ryanair flight early on Saturday morning.
A man in his 50s was taken away and is likely to be put through a fast-track court procedure.
"The flight commander refused to take nine people," police spokesman Peter De Waele told VTM Nieuws. "One of them made a crazy joke and starting calling out 'Allahu Akbar.'"
All the luggage also had to be removed from the plane to be examined by bomb squad sniffer dogs.
Security at the airport has remained tight ever since it and the city's metro station came under attack in April 2016, causing the deaths of 32 people.
Ryanair has repeatedly insisted that it will not tolerate unruly or drunken behaviour on its aircraft following a number of incidents, many of them in the UK.
The airline has already banned UK customers from drinking duty-free alcohol on board.
More than half of cabin crew who responded to a survey said they had witnessed disruptive drunken passenger behaviour at UK airports, according to media reports.