Authorities in Iran have released a top actress who was arrested last month after expressing solidarity with anti-government protesters.

Taraneh Alidoosti was pictured being greeted by friends outside Tehran's Evin prison, her hair uncovered.

The 38-year-old star was freed on bail after being accused of "posting inflammatory content".

She had posted a picture on social media without a headscarf and condemned the first execution of a protester.

Many Iranian actors, musicians and other celebrities have publicly backed the protests against the clerical establishment.

They erupted almost four months ago following the death in custody of Mahsa Amini, a 22-year-old woman who was detained by morality police for allegedly wearing her hijab, or headscarf, "improperly".

Authorities have portrayed the protests as foreign-backed "riots" and responded with lethal force.

So far, at least 516 protesters have been killed, including 70 children, and 19,250 others arrested, according to the Human Rights Activists' News Agency (HRANA). It has also reported the deaths of 68 security personnel.

Two protesters were executed last month after being convicted of the vaguely-defined national security charge of "enmity against God".

Human rights groups condemned their trials as gross miscarriages of justice. They were reportedly tortured into confessing and deprived of access to lawyers of their choosing.

Days before her own arrest on 17 December, Ms Alidoosti had urged people to speak out in response to the execution of the first protester, Mohsen Shekari.

"Every international organisation who is watching this bloodshed and not taking action is a disgrace to humanity," she wrote on her Instagram account, which had millions of followers before it was disabled.

In November, she had posed with her hair uncovered, holding a sign saying "Woman, life, freedom" - the main slogan of the protest movement.

Iran's state news agency, Irna, reported that Ms Alidoosti was arrested for failing to provide "any documents in line with her claims".

Ms Alidoosti is one of Iran's most successful actresses. She starred in The Salesman, which won an Academy Award in 2016 for the Best International Feature Film.

She has paused her career to support the families of protesters killed in the crackdown and has previously vowed to remain inside Iran at any price.

Two other Iranian actresses, Hengameh Ghaziani and Katayoun Riahi, were arrested in November for supporting the protests. They have also been released on bail.

In a separate development on Wednesday, the Iranian government vowed to give a "decisive response" after the French satirical magazine Charlie Hebdo published a series of cartoons mocking Supreme Leader Ayatollah Ali Khamenei, a Shia Muslim cleric who has the final say on all state matters.

Charlie Hebdo said it had received more than 300 such cartoons and "thousands of threats" after it launched a competition last month in order to "support the struggle of Iranians who are fighting for their freedom".

"The insulting and offensive action of a French publication in releasing cartoons against [Iran's] religious and political authority will not be left without an effective and decisive response," Foreign Minister Hossein Amir-Abdollahian tweeted.

Meanwhile, Iran's Supreme Court upheld death sentences handed to two men who were convicted of "corruption on Earth" over the alleged killing of a paramilitary member in Karaj in November.

The court rejected the appeals of Mohammad Mehdi Karami and Seyed Mohammad Hosseini, who have both alleged that they were tortured into making false confessions. Retrials were ordered for three co-defendants sentenced to death in the same case, including Hamid Ghare-Hasanlou. (BBC)

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