Film star Taraneh Alidoosti, who was jailed for two and a half weeks after expressing support for Iran's protest movement, was released on bail on Wednesday.

The 38-year-old star of Asghar Farhadi's Oscar-winning "The Salesman'' was among several celebrities to support for nationwide anti-government protests and to criticize the authorities' violent clampdown on dissent.

What was the actress arrested for?

Alidoosti posted at least three messages voicing support for the protest movement on her Instagram account, which was disabled soon afterward.

One of the messages had expressed solidarity with the first man to be executed on charges connected to a wave of protests precipitated by the death of a woman in police custody.

"His name was Mohsen Shekari," Alidoosti wrote on an account that has about 8 million followers. "Every international organization who is watching this bloodshed and not taking action is a disgrace to humanity.''

Rights groups and celebrities had called for Alidoosti's release.

What are the protests about?

The protests were triggered by the death of 22-year-old Jina Mahsa Amini, an Iranian Kurd who was arrested for allegedly violating the country's strict dress code.

Demonstrations following her death in custody, described as "suspicious" by Amnesty International, have also been fueled by wider pent-up public anger about economic problems and social restrictions.

The protests have escalated into calls for the overthrow of clerical rule in the Islamic Republic, presenting one of the greatest challenges to its leaders since the 1979 revolution.

The hard-line regime, which replaced the more West-leaning and secular shah, quickly imposed policies including Islamic Shariah law and made headscarves mandatory for women in public.

Protesters have set alight banners of supreme leader Ayatollah Ali Khamenei, while women have walked down streets without wearing headscarves in a gesture of defiance.

Iranian authorities say hundreds of people, including security force members, have been killed. Thousands have been arrested, with officials describing the protests as "riots" and accusing hostile foreign powers and opposition movements of stoking the unrest.