Some 80 per cent of prisoners held in Egypt's Al-Aqrab prison began a hunger strike in September to protest human rights violations against them, a rights group has said.
The Association of the Prisoners' Families said in a statement on its official Facebook page that among other complaints, prison authorities had denied detainees family visits for more than a year.
It noted that as a result "the prisoners were forced to eat the prison food which caused them to be poisoned more than once", adding that the prison administration has also prevented them from exercising; some have not seen the sun for six months.
The association accused the prison administration of failing to provide the prisoners with health care, as most of them are elderly and chronically ill.
It warned that the prisoners were dying slowly while "some have been held in solitary confinement for nearly four years".
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There is no official data on the number of detainees in the prison, but Egyptian human rights activist Ezzat Ghoneim told the Anadolu Agency that "the number is between 1,000 and 1,200 prisoners, while the other inmates are held on criminal charges".
Complaints from the prisoners' families have increased in recent months.
According to the prisoners' relatives, the detainees including Muslim Brotherhood leaders launched a hunger strike in late September to protest ill-treatment.
The Egyptian interior ministry has made no comment.