An anti-Islam video posted online by a French teenager has sparked death threats, a hate campaign and an intense debate on the right to blasphemy, including at the top level of the French government.

How did an Instagram post by a 16-year old become a matter of national controversy?

Euronews looks into the case and its implications for France.

What's in the controversial video?

On January 18, 16-year old high school student Mila was live on Instagram, chatting with her followers.

One of them was flirting with her and when the LGBT teen rejected his advances, he accused her of racism.

Mila replied that she wasn't racist but merely against "all religions".

In a subsequent video published as an Instagram story, Mila said :

"There is only hatred in the Koran (...) There are still people who are going to get upset, I clearly don't give a damn, I say what I want, what I think. "

She also used insulting and crude language throughout the video.

The video quickly became viral, prompting death threats and an online hate campaign against Mila, forcing the teenager to drop out of school.

What were the initial reactions?

The public prosecutor's office subsequently opened two separate investigations, one in connexion with the death threats received by the teenager; and the other one to determine whether her comments constituted 'incitement to racial hatred', which is banned under French law, unlike blasphemy, which is legal.

On Twitter, thousands offered their support to the high-school student under the hashtag #JeSuisMila ('I am Mila') while the rival #JeNeSuisPasMila ('I am not Mila') also gained momentum.

Right-wing politician Nicolas Dupont-Aignan tweeted: "Shame to the Prosecutor's office who is treating the victim and her aggressors on an equal footing"

"Let's support Mila against the Prosecutor's office because she dared to criticise Islam. It is those who threaten her who shall be condemned! "

"Islam is a religion. Religion is an opinion. An opinion can be subjected even to the most insulting criticism. Without free speech, France would no longer be France. Let's not be muzzled!" tweeted far-right politician Julien Odoul of the Rassemblement National Party

Abdallah Zekri, the general delegate of the French Council for Muslim Worship (CFCM), said on Friday that while he was against the death threats, the teenager had been looking for trouble.

"Sow wind, reap storm," Zekri told French Sud Radio.

"She was looking for it, she should accept the consequences," he said. "The words she used, the insults she said, I can't accept them".

But Mohammed Moussaoui, CFCM chairman, said in a tweet that "nothing justifies the death threats against a person, no matter how serious her comments were".

How did the government become embroiled in the controversy?

Justice Minister Nicole Belloubet came under fire earlier this week for saying that insulting religion was "against freedom of conscience".

"In a democracy, death threats are unacceptable (...) Insulting religion is obviously an attack on freedom of conscience, it is serious, but it has nothing to do with a death threat", the Minister told Europe 1 radio.

The comments sparked indignation across the political spectrum.

Former Socialist Minister Laurence Rossignol said Belloubet deserved a "zero in constitutional law."

"In France, it is forbidden to insult the followers of a religion but one can insult a religion, its figures, its symbols," Rossignol tweeted.

Belloubet admitted on Wednesday her comments were "clumsy" and said she wasn't questioning the right to criticize religions.

"The offence of blasphemy does not exist in this country and it will never exist under the authority of this government", Interior Minister Christophe Castaner told French senators.

Why is it so sensitive in France?

The controversy is reminiscent of the tensions surrounding the blasphemous cartoons published by satirical magazine Charlie Hebdo.

Five years ago, on January 7, 2015, two gunmen killed 12 people at Charlie Hebdo. They claimed to be avenging the magazine's publication of cartoons of the Prophet Mohammed, which were deemed offensive by many Muslims.

"We avenged the Prophet Mohammed. We killed Charlie Hebdo!", they shouted triumphantly as they ran through the streets.

The attack was the first in a series of assaults that have claimed more than 250 lives since 2015, mostly at the hands of young French-born jihadists.

On social media, many users are drawing a parallel between the viral hashtag #JeSuisCharlie that grabbed world headlines in 2015 and #JeSuisMila.

What's next for Mila?

On Thursday, the public prosecutor announced that the case against Mila for incitement to hatred was dropped while the investigation on the death threats she received continued.

"The investigation showed that the comments broadcast, no matter their outrageous nature, were intended solely to express a personal opinion towards a religion, without the desire to exhort hatred or violence against individuals because of their origin or their belonging to this belief community", public prosecutor Jérôme Bourrier said on Thursday.

But the teenager still hasn't found a school able to guarantee her security.

"What I see today is a 16-year old teen who only exercises her constitutional right acquired during the French revolution (...) and she cannot go to school anymore, we cannot find a school for her, she receives thousands of death threats, she is insulted...and not a single human rights organisation has reacted in the past ten days," her lawyer Richard Malka told French television.