(Bloomberg) -- France was put on the highest terrorist alert after one of the country’s deadliest attacks since World War II killed at least 12 people in shootings at the office of satirical weekly Charlie Hebdo in eastern Paris.

Two people dressed in black and carrying firearms, including AK-47 Kalashnikov rifles, entered the offices of the magazine on rue Nicolas Appert, shooting at random. At least one shouted “Allahu Akbar,” or “God is great” in Arabic. The magazine’s most renowned cartoonists -- Cabu, Charb, Tignous and Wolinski -- were among the dead, the Paris prosecutor’s office said. Eight people were injured. Four of them are in critical condition. The shooters remain at large.

“France is in a state of shock after this terrorist attack,” French President Francois Hollande told reporters. “An act of exceptional barbarity has been perpetrated against a newspaper, against liberty of expression, against journalists.”