Iran revolution anniversary celebrations
Iranian President Hassan Rouhani waves to the crowd during a rally in Tehran's Azadi Square (Freedom Square) to mark the 37th anniversary of the Islamic revolution Atta Kenare/AFP/Getty

The mother of a former BBC journalist arrested in Iran has written an impassioned letter to President Hassan Rouhani, telling him 'you owe me'.

Safoora Tofangchiha, whose son Bahman Daroshafaei was arrested in Tehran on 3 February, wrote to Rouhani pleading for Daroshafaei's releases after he was reportedly taken into custody after being interrogated.

In a letter shared by Iran Wire, Tofangchiha wrote: "I am Bahman's mother. Bahman Daroshafaei. A week ago, a few men were here, waiting for me to hug my son and say goodbye. The men took him away. They didn't tell me where they were taking him, they didn't tell me who they were, why they were taking him, or what they wanted from him.

"I really don't want to write anymore, because I don't think you need to be a professional writer to write about an injustice. But my daughter has asked me to write two more paragraphs.

"Mr Rouhani, if I hadn't voted for you I wouldn't even write those two paragraphs. I'm writing to you, because I think you owe me. Like you owe millions of Iranians who voted for you.

"You know better than anyone else that we didn't vote for you just to lift the sanctions. That was important, and thank God they were lifted. But we voted for you to keep the hope alive, to have more justice, to have more kindness in our society, to stop the brain drain and to help our youth build our country."

Daroshafaei is believed to have spent the past week in solitary confinement.

Following a stint at BBC's Persian service, Daroshafaei spent time working as a translator, most recently translating A Bear Called Paddington from English into Arabic.

Her letter added: "Mr Rouhani, I know you are a busy man. You are the president, and it's the anniversary of the 1979 revolution. Incidentally you owe me because of that as well. My son's name is Bahman [the Persian month when the revolution took place]. He's been in solitary confinement for a week for doing no wrong. May God release all prisoners."

No official reason has been given for Daroshafaei's arrest, but it comes just weeks ahead of the country's Assembly of Experts election on 26 February.