UN blasts 75 death sentences in Egypt, calls trial 'unfair'
Michelle Bachelet said the Cairo Criminal Court's verdict were the result of "an unfair trial".
"I hope that the Egypt Court of Appeal will review this verdict and ensure that international standards of justice are respected by setting it aside," she added.
The case in question involved 739 defendants who faced charges ranging from murder to damaging property. Among those convicted for life sentences were Mohammed Badie, the head of the Muslim Brotherhood in Egypt.
The charges relate to the 2013 sit-in at Rabaa Square that was staged by supporters of the deposed former president Mohammed Morsi and was violently put down by Egyptian security forces, with nearly 1,000 killed.
Morsi was ousted in a coup by Egypt's current President Abdel Fattah el-Sisi, following days of demonstrations against his tenure.
Amnesty International and Human Rights Watch say at least 40,000 people were arrested in the first year after Morsi's ouster on 3 July, 2013.
Egypt's courts have sentenced hundreds of them to death or lengthy jail terms after speedy mass trials that human rights groups said made a mockery of due process.
Meanwhile, no members of the Egyptian security forces or Cairo authorities have been held accountable for the Rabaa massacre.
Agencies contributed to this report.
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