( CNN ) -- An Iranian court may render the final verdict Thursday in the case of Sakineh Mohammedie Ashtiani , sentenced to death by stoning in Iran for allegedly committing adultery . That case was placed under review after her attorney , Mohammad Mostafaei , helped launch a worldwide campaign to clear her . Now , as Ashtiani 's two children wait to hear word of their mother 's fate , Mostafaei 's family must also await word of his . That 's because Mostafaei , a prominent human rights lawyer , was being held Wednesday at a detention center in Istanbul , Turkey , where he has requested asylum , said Metin Corabatir , a representative in Turkey for the U.N. High Commissioner for Refugees . He allegedly entered the country with improper documentation , the agency said . Turkey does not require visas for citizens from neighboring Iran to enter the country . As a result , it is the first place hundreds of Iranians fled to after the Iranian government cracked down on opposition activists and critics over the past year . Human rights groups are urging officials to grant his asylum request because they say he could be in grave danger if he is forced to return to Iran . There is no word yet on whether any nation is willing to accept him . Mostafaei went into hiding July 24 , after facing a lengthy interrogation at Iran 's notorious Evin prison , the same day rallies were being held worldwide to draw attention to the Ashtiani case . His wife and brother-in-law were reportedly arrested that night at his office in Tehran as they tried to gather his belongings . The Iranian government has since released Mostafaei 's brother-in-law , but human rights groups said they are holding his wife as collateral until Mostafaei returns . In a now widely circulated open letter reportedly penned by Mostafaei and posted on the internet , the lawyer accused Iranian authorities of holding his wife `` hostage . '' He also explained why he made the painful choice of leaving his wife behind . `` Despite the arrest of the person I love most in my life , I decided not to ever set foot in a judicial office where the interrogators do not abide by any basic laws , '' he wrote . `` Hostage taking is never legal '' Mostafaei said . `` I decided not to appear unless the interrogator 's office tries hard enough to come and arrest me in my silo that I have built for myself . '' Mostafaei was asked by CNN in early July if he was worried about his safety after bringing so much attention to Ashtiani , who was convicted of adultery in 2006 and condemned to die by the brutal method of stoning . Mostafaei told CNN that he knew the risks -- he had been detained briefly after Iran 's post-election turmoil in June 2009 -- but that would not stop him fighting for human rights . But it was that very fight that forced him to flee the country he calls home . As part of that open letter , Mostafaei cried out to the Iranian government -- and to God -- for the strange twist in his fate . `` For the past few years all my thoughts have been towards saving people who did not deserve to die . '' he wrote . `` I was so occupied with saving these people that I hardly got to see my dear wife and daughter . ... And for someone who has always worked towards justice and the interests of the Islamic Republic , is this the way I am paid back for my God-loving and human-loving actions ? '' `` I leave you and your interrogator at the mercy of God , the creator , '' he continued . `` I hope that you wo n't let my child cry for her mother , not eating food and wanting her mother back . She needs to hug her mother . If through this separation from her mother she gets hurt , it 's a sin that you have committed . '' The Iranian government has not commented on the detention of Mostafaei 's wife . Meanwhile , human rights activists are urging the international community not to forget Ashtiani , who may soon die . Nor the man who tried to set her free . CNN 's Ivan Watson and Moni Basu contributed to this report .
Prominent human rights lawyer Mohammad Mostafaei is being held in Turkey . The United States has called for the release of all political prisoners and urged Iran to end its "campaign against civil society." In an open letter , he appeals for the well-being of his family .