There are reports of "intense" gunfire in a car chase northeast of Paris, near Charles de Gaulle Airport.
French police had been hunting suspected gunmen Said, 34, and Cherif Kouachi, 32, in houses and a forest to the north east of Paris, after 12 people died in an attack on the offices of satirical magazine Charlie Hebdo on Wednesday.
Police are now chasing a vehicle on the A2 motorway.
There are reports too that a hostage or hostages have been taken.
The manhunt homed in on a region north of Paris as the nation mourned the dozen people murdered, while more than 88,000 security forces were deployed on the streets of France.
The authorities said they feared a second strike by the Kouachi brothers and distributed their portraits with the warning “armed and dangerous”.
BREAKING INTENSE GUNFIRE HEARD NEAR Paris-Charles-de-Gaulle AIRPORT - airplanes currently over CDG airport pic.twitter.com/WPUQCiCllL— AIRLIVE (@airlivenet) January 9, 2015