By Jonathan Davies

Stock markets in France have remained stable despite yesterday (Wednesday)'s horrific attack on Charlie Hebdo magazine which saw 12 people killed.

The Cac 40 index is up 1.80% for the day which has been declared a national day of mourning in France.

Manhunt

Today (Thursday) a massive manhunt is under way in Paris for two of the three men who carried out the attack on the satirical, cartoon-based magazine Charlie Hebdo.

Police released photos of two brothers, Cherif and Said Kouachi, suspected over carrying out the attack. The third suspect, 18-year-old Hamyd Mourad, handed himself in.

French police have said a number of arrests have been made relating to the massacre. Those arrested are believed to have connections with the Kouachi brothers, who are reported to have robbed a petrol station in the north east of France.

Another shooting took place at metro station in the south of Paris this morning. One police officer was killed by a gunman. It is not clear whether or not the incident is linked to yesterday's atrocities.

The three men stormed the Charlie Hebdo office in Paris, shouting Islamic slogans. Charlie Hebdo's editor-in-chief Stephane "Charb" Charbonnier, and some of the magazine's most recognised cartoonists were among those killed.

Two police officers were also killed. One was shot on the street outside the Charlie Hebdo office with eye witnesses describing it not as a 'killing' or 'murder' but as an 'execution'.

It is not the first time Charlie Hebdo has been attacked. In 2011, the offices were attacked with a fire-bomb. The magazine is known for its highly-critical cartoons. Believed to be the cause of the attack is a cartoon which mocked the prophet Muhammed. Witnesses say the gunmen shouted "we have avenged the Prophet Muhammad" as they carried out the attack.

Tributes

There has been international outcry and condemnation over the attack. Tens of thousands of people took to the streets and central squares of Paris and other cities around France to pay tribute to those killed and stand firm in defence of freedom of speech and expression.

French Prime Minister Hollande yesterday described the attack as an 'attack of freedom of speech'.

People took to Twitter with the hashtag #JeSuisCharlie in support and tribute to those killed and Charlie Hebdo. As the day went on, #JeSuisCharlie became flooded with cartoons depicting a more modern approach to the 'the pen is mightier than the sword' phrase.