Tens of thousands of people, French or otherwise, have tweeted the message "Je Suis Charlie" ("I am Charlie") to express their support for the victims of the terrorist attack on Parisian satirical weekly Charlie Hebdo.

The message, typed in various styles and fonts, has been tweeted more than 70,000 times just hours after the shooting in the 11th district of Paris unfolded at around noon on Wednesday, BBC reported. At least 12 people, including two police officers and the top cartoonists of Charlie Hebdo, were killed in the attack.

By around midnight on Thurday the #JeSuisCharlie hashtag had been used 216,000 times, ABC News said.

Even the US embassy in France has added #JeSuisCharlie to its Twitter picture.

Rallies are also being planned for major cities across France on Wednesday evening.