France’s largest airport is operating a reduced service amid a nearby ongoing siege involving the Charlie Hebdo shooting suspects.
Up to two of the four runways at Charles de Gaulle Airport are affected, and at least two planes have been diverted from landing there.
An Air France spokeswoman said the airport remained open but that aircraft had been warned by air traffic controllers that helicopters involved in the search were flying at low altitudes in the area.
The suspects are believed to be cornered in the premises of a printing firm in Dammartin-en-Goele, 25 miles from the capital, after stealing a car earlier. Police helicopters are circling the airspace.
At least two people were feared dead after shots were fired during the operation, but officials have denied reports of fatalities. Police have confirmed a hostage - believed to be a woman - has been taken.
Schools in the area are on lockdown and residents are being asked to stay in their homes with the doors locked and the lights turned off.
Brothers Said and Cherif Kouachi are suspected of murdering 12 people at the Paris offices of satirical newspaper Charlie Hebdo on Wednesday.