#JeSuisCharlie messages flood social media after attack

Soon after gunmen killed at least 12 people at the French satirical newspaper Charlie Hebdo, #CharlieHebdo and #JeSuisCharlie — "I am Charlie" in English — were trending on Twitter in a sign of solidarity for victims.

In the hours since the midday attack Wednesday, there have been 176,000 tweets featuring #JeSuisCharlie, according to Topsy, which tracks Twitter analytics.

In the last hour, 77,000 have used the hashtag.

Hours before the attack, the weekly had tweeted a caricature of Islamic State leader Abu Bakr al-Baghdadi. No group has claimed responsibility for the attack in Paris.

French President François Hollande tweeted, "No barbaric act will never extinguish the freedom of the press. We are a united country."

Leaders from the U.S., England and Germany also responded. The White House quoted President Obama, saying "Our thoughts and prayers are with the victims of this terrorist attack."

The U.S. Embassy in France also changed its Twitter photo to "Je Suis Charlie."

Journalist Piers Morgan offered, "The pen is mightier than the sword."

In England, U.K. Prime Minister David Cameron tweeted, " We stand ...squarely for free speech and democracy."

Jessica Pires, the wife of former Arsenal and France midfielder Robert Pires, simply wrote R.I.P. on Instagram.

Germany's chancellor offered her opinions on the attack, Reuters reports.

It wasn't the first time the newspaper was attacked. In 2011, the offices were bombed in response to a cover that featured the prophet Mohammed.

The publication was well known for images that pushed the bar.

On Twitter, users offered condolences and said the terror attacks wouldn't prevent freedom of speech.

Gallery: Photos of terror attack in Paris

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