The letter, published on February 26, says protesters arrested following the 2009 presidential election -- including political activists, university professors, journalists, and students -- do not enjoy the same rights as other prisoners.
Amin Ahmadian, husband of jailed student activist Bahareh Hedayat, told Radio Farda on February 27 that he was last allowed to visit his wife three months ago, and has been able to speak to her by telephone only once in the past five months.
Hedayat, a senior member of Iran's largest pro-reform student group, the Office to Foster Unity, was arrested in December 2009. She has been sentenced to 9 1/2 years in jail.
Ahmadian, who is one of the signatories of the letter, said that in December his wife was diagnosed by a prison physician with gall stones but was not given a release for medical treatment.
Meanwhile, a number of students at the Babol Noushirvani University of Technology in northern Iran were arrested during opposition rallies in February.
Student activist Salman Sima told Radio Farda that one student who was recently released said those who were arrested had been beaten in detention while blindfolded.
Iranian Science Minister Kamran Daneshjou said on February 26 that any faculty member or student who cooperates with the "sedition," a reference to Iran's opposition Green Movement, is working with counterrevolutionaries and will be "treated severely."
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