Police in Belgium have detained a further six people in connectionwith an alleged plot to target Brussels on New Year's Eve, prosecutors say.
The six were detained during raids at locations in and around the Belgian capital on Thursday.
Two men had been arrested earlier in the week, and the mayor of Brussels has cancelled the New Year's festivities.
French authorities say more than 100,000 police are being deployed across France to ensure security.
Paris will see its biggest public gathering since the deadly attacks there last month, but the city's usual firework display will not take place.