Egypt in crisis
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Syrian refugees in Egypt often face illegal detention or deportation, Amnesty International says.
The authorities are holding hundreds of Syrian refugees in deplorable conditions, among them children as young as one, the rights group says.
Some of them are accused of being Muslim Brotherhood supporters, and being complicit in the recent political violence in Egypt, Amnesty said.
The Egyptian authorities have not yet responded to the findings.
The UN estimates that by the end of 2014 more than eight million Syrians could have been forced from their homes, and the number of refugees outside Syria could hit 5.2 million.
Syria's civil war began in the wake of the Arab Spring uprisings in 2011, which saw Egypt's long-time President Hosni Mubarak toppled.
"The Egyptian authorities have a duty to provide protection to anyone who has fled the conflict in Syria and is seeking safe refuge in their country," Sherif Elsayed Ali, Amnesty International's head of refugee and migrants' rights, said in a statement.
"At present Egypt is failing abysmally to meet its international obligations to protect even the most vulnerable refugees.
Sending refugees back to a bloody conflict zone is a serious violation of international law”Sherif Elsayed AliAmnesty International
"Instead of offering vital help and support... the Egyptian authorities are arresting and deporting them."
Prior to the military ousting of President Mohammed Morsi, Syrian refugees told Amnesty International that they felt safe and protected in Egypt.
However, in July and August, following Mr Morsi's removal, their situation turned for the worse when some public figures and parts of the mainstream media started accusing Syrians of being supporters of the Muslim Brotherhood and taking part in pro-Morsi demonstrations, Amnesty said.
"My kids can't play outside anymore. They are cursed by the other kids, told really bad words… There were 1,700 [refugees] living in the area, but now there are no more than 500," a Syrian refugee in a suburb of 6 October City outside Cairo told Amnesty this month.
The campaign group's report - "We cannot live here any more": Refugees from Syria in Egypt - says this change in atmosphere has prompted some Syrians to try to reach Europe by boat.
Amnesty says many detainees were stopped trying to reach Europe by boat
Many of those detained had been stopped whilst trying to make the hazardous crossing across the Mediterranean Sea.
The report says the Egyptian navy has intercepted around 13 boats since August and, according to UN refugee agency, arrested 946 people, 724 of whom remain in detention.
Several lawyers said they were prevented from representing refugees detained in police stations along the Mediterranean coast, the report said.
Scores of Syrian children are being detained, many without their parents and some detainees have been held in unsanitary conditions in police stations without food or medical assistance, it said.
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Where Syrian refugees are
794,450 in Lebanon
544,392 in Jordan
504,415 in Turkey
196,843 in Iraq
125,893 in Egypt
4.25 million others displaced inside Syria
( Source UNHCR and Ocha)
Tent city: Syrian refugees in Jordan
During a visit to a police station in the port city of Alexandria last week, Amnesty researchers found about 40 Syrian refugees unlawfully and indefinitely detained, including 10 children, the youngest of whom were one-year-old twins held there since 17 September.
Several detainees told Amnesty International that police threatened to transfer them to Al-Khalifa prison in Cairo unless they signed papers accepting deportation to countries in the region or back to Syria.
Lawyers told researchers that in at least two instances refugees were collectively deported back to Damascus, Amnesty says.
Earlier this month a group of 36 mostly Palestinian refugees from Syria were deported to Damascus.
Amnesty said many of them are believed to have been detained in Damascus at the Palestine Branch of Syrian Military Intelligence, one of the most feared sections of Syria's secret service.
"Sending refugees back to a bloody conflict zone is a serious violation of international law," Mr Ali said.
The report was also critical of new restrictions on Syrian nationals entering Egypt, requiring them to have a visa and security clearance before arrival.