Actors James McAvoy, Claire Danes and Ben Stiller have joined a host of Hollywood stars in calling for the immediate release of 11 prominent human rights defenders in Turkey.

More than 20 celebrities – including Zoë Kravitz, Tim Roth, Mark Ruffalo, Whoopi Goldberg, Zach Galifianakis and Marisa Tomei – have signed a letter sent by Amnesty International USA to the Turkish ambassador.

The letter said: “The frequent attack on human rights defenders in Turkey is unjust and simply not acceptable.”

They join a host of other celebrities including Patrick Stewart and Peter Gabriel who have called for the release of the activists.

Today marks one hundred days since the wrongful arrest of 10 activists – including İdil Eser, the Director of Amnesty Turkey – at a meeting near Istanbul on 5 July. Taner Kılıç, Amnesty’s Turkey Chair, was arrested the month before and remains in detention. On 4 October, a prosecutor filed an indictment calling for jail terms of up to 15 years for all 11 activists on trumped-up terrorism charges.

Amnesty is leading a global demand for the immediate and unconditional release of the activists in Turkey.

John Dalhuisen, Amnesty International’s Europe Director, said:

“One hundred days ago, our colleagues were locked up for standing up for human rights. Every passing day further exposes the long reach of the post-coup crackdown and the deep flaws in Turkey’s justice system.”

In the coming days, Amnesty activists in more than 25 countries will hold more than 200 parties and stunts to mark İdil‘s 54^th birthday on Saturday 14 October. These will range from a birthday party in the European Parliament, to a press conference in a makeshift prison in Madrid. Full-size paper cutouts of Idil will be present to highlight her absence.

The activists are accused of assisting a variety of ‘armed terrorist organisations’ with diametrically opposing ideologies. The charges against them include outlandish claims that standard human rights activities such as appealing to stop the sale of tear gas, making a grant application or campaigning for the release of hunger striking teachers were carried out on behalf of terrorist organisations.

After three months, the investigation has failed to provide any incriminating evidence to substantiate the prosecutor’s charges, nor has it shown how the supposedly secret meeting relates to terrorism in any way.