The European Union said staff working in kitchens of its new building in Brussels have fallen ill and been evacuated after a ventilation malfunction filled the air with fumes.
The European Council said "a technical issue" with the ventilation "producing noxious fumes in the kitchens, has led to a number of kitchen staff falling ill".
Several fire service and police vehicles were parked in front of the so-called Europa building.
Some kitchen staff were evacuated to the old EU headquarters next door.
The EU said an investigation has been launched and that the incident will not prevent the October 19-20 summit of EU leaders from taking place.