Throughout this time, he continued working as a journalist and wrote several letters to the Iranian authorities protesting against prison conditions. He was released in September 2014.

“When he was in prison and being tortured, he contracted the flu and the prison doctor prescribed him two shots of penicillin. They gave him both shots at the same time, which meant he suffered from convulsions and fainting."

Mehdi Mahmoudian played an important role in exposing the atrocities committed at Kahrizak Detention Center following the disputed 2009 presidential election. Many detainees were beaten and tortured; several were killed. He also published numerous reports on the secret burial of detainees who died under torture. He was arrested at his home on September 16th 2009 and spent 90 days in solitary confinement at Cell Block 209 at Evin Prison, where he was beaten and tortured.

Following his release, he suffered from migraine headaches, epilepsy and acute pulmonary infection as a result of his treatment while in prison: he was frequently forced to be outside in the freezing cold without any clothes on. Prison officials attempted to pressure Mahmoudian to confess and testify against Emadeddin Baghi, a human rights activist and the founder of the Committee for the Defense of Prisoners' Rights.

“When he was in prison and being tortured, he contracted the flu and the prison doctor prescribed him two shots of penicillin,” says Fatemeh Alvandi, Mahmoudi’s mother. “They gave him both shots at the same time, which meant he suffered from convulsions and fainting. When I went to visit him, his friends told me they had to shake him like a drink shaker to bring him back to consciousness because they thought this was the only way the penicillin would be absorbed. After that he would faint regularly.”

When his condition deteriorated significantly, prison officials wanted to move him to a hospital in shackles. He refused. In a letter to the prosecutor, he wrote, “It’s been seven months since three specialists at the prison clinic requested that I be sent to hospital outside the prison for a CT scan and cardiac tests, but the permit has yet to be issued.”

While in prison Mahmoudian protested against the execution of five Kurdish political activists and was banished from Evin. In April 2010, he was taken to Rajaie Shahr Prison in Karaj, which houses inmates on death row and is renowned for its brutal conditions. For two and a half years his father was too frail to visit him and his mother, who was also very old, had to use public transport once a week to see him.

His trial took place on May 16th 2010, at the Revolutionary Court presided over by Judge Moghisei, who sentenced him to five years in prison. He appealed but the appellate court under Judge Zargar upheld the original verdict. While in detention, Mahmoudian wrote open letters to Iran’s authorities, which resulted in yet more pressure being placed on him. In one letter he described the inhumane conditions at Rajaie Shahr Prison: “Despite having a capacity of less than 1,000 prisoners, it currently holds approximately 5,000 inmates. This is unbelievable; more than 1100 of them have a death sentence. As I am writing this report, there are 1,117 death row inmates. According to official data provided by the judiciary, the average time an individual remains on death row prior to its implementation is five years meaning that an individual on death row is tortured for an average of five years before their execution.”

In a second open letter to Ayatollah Khamenei, he wrote about sexual assaults taking place in the prison. These letters and the fact that he continued to pursue his work as a journalist from within the prison led to him being transferred a second time. In January 2012, Revolutionary Guards interrogators took him to Section 2A of Evin Prison, an area under the Guards control. According to reports, he was beaten and humiliated by guards on the journey from Karaj to Tehran. His condition was so serious that when he arrived, he was immediately taken to the prison clinic and given an oxygen mask. The same day Intelligence Ministry agents detained his mother, who was told to stop talking to media outlets. After two and a half years in detention, Mahmoudian was granted his first medical furlough on March 21st, 2012. He was freed on September 3rd 2014, having served his sentence.

According to Kaleme newspaper, he should have been released on August 21st but prison officials kept him in for an additional 12 days.