Charlie Hebdo: All you need to know about the terrorist attack in Paris

Masked gunmen shouting "Allahu akbar!" stormed the Paris offices of a satirical newspaper 'Charlie Hebdo' on Wednesday, killing 12 people, including the paper's editor, before escaping in a getaway car. It was France's deadliest terror attack in living memory. UN Secretary-General Ban Ki-Moon describing the assault said, "It was a horrendous, unjustifiable and cold-blooded crime." Here's the timeline of events along with the world leaders' reaction.