When he was found he had not eaten for three weeks and had been tortured, said a man named Abou Hamad, who cared for Mr. Gamienbay at his house in the area in the days before he died.
The Egyptian government began military operations in August to root out extremists and get Sinai under control. But despite an increased security presence, criminal gangs in Sinai continue to take migrants and asylum seekers hostage en route to Israel. They are held for ransom and often tortured.
“This is one of the most serious human rights concerns in Egypt and it’s not being addressed,” said Nicholas Piachaud, North Africa campaigner for Amnesty International. “It’s a tragedy which has unfolded across many different countries and is playing out on an international scale but being ignored by the international community.”
Sub-Saharan migrants, refugees and asylum seekers began moving northward, aiming to enter Israel, around 2006, said Shahar Shoham, who directs the migrants department at Physicians for Human Rights-Israel, which provides medical treatment for them.
At first they were mostly Sudanese, who paid as much $2,000 to be taken to Israel, said Abou Mahmoud, a Sinai Bedouin who said he used to smuggle them.
But since 2008 they have mostly come from Eritrea, said Ms. Shoham and other experts. It is these Eritreans who have become the main targets of extortion and trafficking.
Meron Estefanos, a human rights activist and radio presenter in Sweden for Radio Erena, which broadcasts in Eritrea and via satellite around the world, said that in some cases criminals lured young Eritreans seeking asylum in Ethiopia into crossing Sinai instead, with a promise of better lives in Israel. They then kidnap them, she said.
Over the past 20 months, human rights workers in Egypt, Israel and Europe have documented a disturbing new trend.
Hostages in Sinai say they never intended to go to Israel but were kidnapped in Sudan or Ethiopia on their way to refugee camps and sold to Sinai criminals to be held for ransom.
“We are actually talking about a few hundred in Israel that didn’t plan to come here,” Ms. Shoham said.
The kidnappers are members of the Rashaida tribe in Eritrea and Sudan, or other Eritreans, according to a September report by Europe External Policy Advisers, a research group in Brussels, and Tilburg University, in the Netherlands. The report was based on 104 interviews with hostages, conducted primarily by telephone while they were being held.
Many said they had been kidnapped from refugee camps, including the Shagarab camp, in Sudan, and Mai Aini, in Ethiopia.