Al-Qaeda in Yemen is warning France of more "tragedies and terror" after last week's attack in Paris.
In an online video, the group says it chose Charlie Hebdo as a target, laid out a plan and "financed the operation."
The French magazine's added 2 million copies to its print run - after a special edition sold out this morning.
The front cover of the magazine depicts the Prophet Mohammed holding a sign that says "Je suis Charlie" - a slogan taken up by supporters since the attack a week ago.
The edition's lead editorial said: "For the past week, Charlie, an athiest newspaper, has achieved more miracles than all the saints and prophets combined.
"The one we are most proud of is that you have in your hands the newspaper that we always made."
Profits from the "survivors' issue", which will be printed in French and Italian along with translations in English, Spanish and Arabic in electronic form, will go to the families of victims of the shooting.
Michel Salion, from distributors MLP, is surprised by the interest:
