Police in France have made seven arrests as they hunt for two named suspects over the deadly attack in Paris on staff at a satirical magazine.
The seven, connected to the two main suspects, were detained in the towns of Reims and Charleville-Mezieres, as well as in the Paris area, police said.
Photos were released of two brothers suspected of involvement in the attack.
France is mourning the 12 people killed when Charlie Hebdo was targeted by gunmen shouting Islamist slogans.
A gunman fired on police in the south Paris suburb of Montrouge on Thursday morning, injuring an officer before fleeing, security sources say. It is not known whether the incident is linked to the attack on Charlie Hebdo.
French President Francois Hollande has presided over an emergency cabinet meeting in Paris.
A minute's silence will be observed at midday across the country and the bells of Notre Dame in the capital will toll.
Arrest warrants were issued for Cherif and Said Kouachi, said to be "armed and dangerous". A third suspect has surrendered.
Cherif Kouachi was sentenced in 2008 to three years in prison for belonging to a Paris-based group sending jihadist fighters to Iraq.
A third suspect, 18-year-old Hamyd Mourad handed himself in to police in Charleville-Mezieres. He reportedly surrendered after hearing his name on the news.The victims
- Charlie Hebdo editor and cartoonist Stephane "Charb" Charbonnier, 47, who had been living under police protection since receiving death threats
- Cartoonists Jean "Cabu" Cabut, 76, Bernard "Tignous" Verlhac, 57, Georges Wolinski, 80, and Philippe Honore, 73
- Economist and regular magazine columnist Bernard Maris, 68, known to readers as Uncle Bernard
- Mustapha Ourrad, proof-reader
- lsa Cayat, psychoanalyst and columnist, the only woman killed
- Michel Renaud, who was visiting from the city of Clermont-Ferrand
- Frederic Boisseau, 42, caretaker, who was in the reception area at the time of the attack
- Police officers Franck Brinsolaro, who acted as Charb's bodyguard, and Ahmed Merabet, 42, who was shot dead while on the ground
Source: Le Monde newspaper and other French media