An Iranian musician serving a three-year jail term in Iran bemoaned his sentence and the deplorable conditions of his imprisonment. Since June, Mehdi Rajabian, 27, has been jailed in Tehran’s notorious Evin prison along with his brother, Hossein, a 31-year-old filmmaker, after they were found guilty of “spreading propaganda against the system” and “insulting the sacred” in 2015. For more than a month, the brothers went on a hunger strike in protest over their treatment.

Rajabian’s medical condition deteriorated to the point that authorities released him on furlough and let him be hospitalized in his home province of Mazandaran. He is expected back at Evin on Sunday, but managed to contact the outside world using a smartphone in the hospital. Rajabian communicated with WorldViews via a messaging app, detailing the physical and mental hardship he has endured in recent months.

Starting at the end of October, he and his brother commenced a hunger strike that, despite a few interruptions, goes on. They drink water but refuse food in prison. Rajabian claims to have lost 33 pounds and “40 percent of his vision” during this time. Rajabian says his brother, who is still in prison, is suffering from a kidney infection. In the hospital, Rajabian was treated for internal bleeding in his stomach, among other aliments.

“They did not provide us with medical care,” he wrote of his and his brother’s time at Evin. “We first protested, but because of our protest, they separated me from my brother and they put me in a section with Tanzanian drug-dealers and Somali pirates as a punishment. They banned us from seeing our family or our lawyers.”

. ای زنده ایم... میگذرد.

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Such circumstances are sadly not unusual in the Islamic republic. According to a mid-November news release by the International Campaign for Human Rights in Iran, “at least eight political prisoners are currently on life-threatening hunger strikes in Tehran and Karaj to demand better conditions and reviews of their unjust prison sentences.”

The Rajabian brothers would probably not think of themselves as “political” prisoners. The two were big players in Iran’s underground music scene and managing partners of Barg Music, a popular online music distribution service now blocked by the government. Iranians must pass official censors and obtain government licenses to make music — leaving the duo vulnerable to arrest.

In 2013, the brothers and another partner, Yousef Emadi, were detained by authorities and accused of “spreading corruption” through their unsanctioned music business, as well as for working with female singers, who are prohibited from singing solo under Iranian laws.

Rajabian and his partners complained that they had applied but never received permits for their work, which they argue is not political. At the time of his arrest, Rajabian, who plays the sehtar, a stringed instrument, was composing an album that, in his words, provided a “picturesque atmosphere” of the history of Iran. Hossein’s first feature film, “The Upside-Down Triangle,” which looked at a woman’s right to divorce in Iran, emerged as another reason for their prosecution.

In 2015, they were sentenced to six years in prison and forced to pay a hefty fine.

“The initial trial lasted three minutes and they did not pay attention to what we said and they did not even allow us to hire a lawyer,” Rajabian wrote to WorldViews. “Such courts have always been like this.”

An appeals court in February commuted their sentence to three years; in June, they were summoned to Evin to begin serving their time.

“Expressing yourself through art is not a crime and it is outrageous that the Iranian authorities have resorted to locking up artists and musicians simply for their artistic work,” Philip Luther of Amnesty International told Britain’s Guardian newspaper. “Mehdi and Hossein Rajabian are prisoners of conscience who shouldn’t be forced to spend a single minute behind bars. The Iranian authorities must order their immediate and unconditional release.”

Observers see the imprisonment of the Rajabians as part of a broader judicial crackdown on Iranians in civil society and the arts. On Friday, an Iranian American art gallery manager and his wife were detained at Evin, just the latest in a series of dual nationals to be rounded up on dubious grounds by the Iranian government. The Washington Post’s Jason Rezaian was detained for 18 months on vague espionage-related charges before his release this year.

Rajabian hopes fellow musicians elsewhere will bring attention to his plight.

“I want all artists in the world to protest against this unjust sentence,” Rajabian wrote. “The biggest pain of an artist in prison is to be forgotten.”