Twelve people have been killed after two masked gunmen entered the Paris headquarters of satirical French magazine Charlie Hebdo and opened fire with automatic weapons. Three people are in a critical condition.
President Francois Hollande described it as a terrorist attack.
Speaking at the scene of the attack a short while ago, Hollande said the government had raised the alert level in the capital to its maximum as police hunt for the gunmen, who escaped after the shooting.
The attackers went to the second floor and started firing indiscriminately in the newsroom, said Christophe DeLoire of Reporters Without Borders.
"This is the darkest day of the history of the French press," he said.
Two policemen were among those killed in the shooting, which lasted several minutes after the gunmen entered the magazine's offices and started firing. Graphic footage of a policeman being killed was uploaded on You Tube moments after the shooting, but was taken down shortly after.
The motive for the attack was allegedly due to a cartoon which was published by Charlie Hebdo on Wednesday, poking fun at the ISIS leader.
The offices of the weekly magazine were firebombed in November 2011 after it published a spoof issue that featured the prophet
Mohammed as editor. No one was injured in that attack.
British Prime Minister David Cameron and US President Barack Obama condemned the attack.
SAPA
