Image copyright AFP Image caption Asylum seekers stage a protest by leaning against the fence of the Holot detention centre

For nearly a year Israel has been offering African migrants cash and the chance to go and live in what is supposed to be a safe haven in a third country - but the BBC has spoken to two men who say that they were abandoned as soon as they got off the plane. One was immediately trafficked, the other left to fend for himself without papers.

Adam was 18 when he arrived in Israel in 2011. Attackers had burned down his home in Darfur at the height of the genocide, and he had spent his teenage years in a UN refugee camp in another part of Sudan. With no prospects in the camp and no sign of an end to the conflict in Darfur, he made his way north through Egypt and the lawless Sinai peninsula to Israel.

But Israel - which has approved fewer than 1% of asylum applications since it signed the UN Refugee Convention six decades ago - has not offered asylum to a single person from Sudan. It turned down Adam's application, and last October, when he went to renew the temporary permit allowing him to stay in the country, he was summoned to a detention centre known as Holot, deep in the Negev desert.

This was no surprise for Adam. As most Sudanese and Eritreans in Israel know, it's just a matter of time before they get the call to Holot.

Media playback is unsupported on your device Media caption Adam is from Sudan and now lives in the Holot detention centre

The government calls Holot an "open-stay centre", but it's run by the prison service and rules are strict, including a night-time curfew, which, if broken, will land you in jail.

It's in such an isolated area that there's very little to do and nowhere to go.

I talked to Adam and a group of his friends just outside the gates of Holot, where, at that time, they spent most of their day playing cards or snooker, and eating and cooking in makeshift restaurants.

They told me they took turns to make the hour-long bus ride into the nearest town, Beersheva, where they bought food. The meals served in Holot were insufficient, they said, and contained little meat or protein.

Most of the men there were young - in their 20s or early 30s. Some had been teachers, activists or students in their own countries.

"We are wasting our youth here," Adam says. "If someone lives in Holot, they have no future... You find many people here go crazy."

Since I visited Holot, those makeshift restaurants and game areas have all been demolished on the orders of the government, leaving those inside with even fewer ways to pass the time.

Image caption Holot detention centre is located close to Saharonim prison, where those who refuse to leave Israel may be held indefinitely

Adam will be held in Holot for 12 months. Then he is likely to face a stark choice:

Go home to Sudan

Stay in Israel, but be imprisoned indefinitely

Accept departure to a third country

The Israeli government has deals with two countries in Africa to host its unwanted migrants.

It promises that people who take the option of "voluntary departure to third countries" will receive papers on arrival that give them legal status in the country.

Find out more

Watch Kathy Harcombe's TV report for Focus on Africa on BBC World News at 17:30 GMT, Wednesday 3 February.

As an extra incentive, they're given $3,500 (£2,435) in cash, handed over in the departure lounge of the airport in Tel Aviv.

Israel refuses to name the two African countries but the BBC has spoken to migrants who say they were sent to Rwanda and Uganda.

One is Tesfay, an Eritrean who was flown to Rwanda in March 2015, and he told me that far from being offered legal status, a home and the chance of a job in Rwanda - as he had been promised in Israel - he became a victim of trafficking.

His identity papers - a travel document and a single-entry visa to Rwanda, both issued in Israel - were immediately confiscated at Kigali airport, he says.

Then, along with nine other Eritreans, he was taken to a "guest house". None of them was allowed out. It would be dangerous without papers, they were told. Then, two days after arriving, the men were told it was time to leave.

Image caption Tesfay took this picture of the guest house in Rwanda

"You are going to Uganda. But before you go, you need to pay $150," said a man who introduced himself as John. "Then from the border to Kampala you need to pay again."

Crammed into a minibus, they made the six-hour journey to the Ugandan border, where they were told to get out of the bus.

"When we crossed the border, that's when I understood that we were being smuggled," Tesfay says. "We went on foot, silently. We were being smuggled from one state to another."

As promised by "John", they had to pay another $150 to continue their journey to the Ugandan capital, Kampala.

But inevitably, having entered as illegal immigrants, they were arrested on arrival and put behind bars - after police had relieved them of about half the cash in their pockets, Tesfay says.

With what was left, Tesfay managed to post bail. He was due to appear in court five days later and having already been warned he was likely to be deported to Eritrea - the repressive authoritarian state he had fled in the first place - he decided to take no chances. He paid another smuggler to get him into Kenya, where he is now seeking asylum.

Rwanda has never confirmed that it struck a deal to host Israel's unwanted migrants. The Ugandan government, for its part, has denied outright that such a deal exists - it told the BBC it was investigating how migrants who claimed to have been sent from Israel were entering the country.

The BBC spoke to a man from Darfur who said he was flown to Uganda from Israel with seven others in 2014, before the third country policy became official.

For safety reasons, he asked to remain anonymous.

"None of the things I was promised were given to me," he said. "No documents, no passport, no assistance - nothing. (Israel) just wants to take people and dump them."

Image copyright EPA Image caption Israel fenced the Egyptian border in 2013, reducing the flow of migrants into the country

In October, Israeli immigration authorities said 3,000 asylum seekers had left Israel for a third country. But the BBC has learned that only seven have registered with the UN High Commissioner for Refugees in Rwanda, all of them Eritreans, and only eight, mostly from Sudan, in Uganda.

Meanwhile, there are about 45,000 Eritreans and Sudanese in Israel. The government won't deport them - that would be a clear breach of the UN Refugee Convention, which it signed in 1954. Under the Convention, no-one can be forcibly returned to a country where they have a justified fear of persecution.

But if Israel treats them as refugees at least in this respect, why does it then refuse them asylum?

Foreign Ministry spokesperson Emmanuel Nahshon says the migrants threaten the security, and the identity, of the Jewish state.

"It's obvious that we live here in a situation which is rather complex and complicated. And if you add this element of migrants who come here and who want to stay here - undoubtedly because this is a rich and prosperous country - then it could become also a challenge to our identity here in Israel.

"It's not only about the 45,000 or 50,000 people that already are here in Israel, it's about the potential. Because those people tell their friends and families back home - 'Look, this is a very nice place. Do come over.'"

Image caption Migrants on a street in Tel Aviv

And, of course, in Israel there is also the ever present issue of security.

"Open borders through which migrants can pass mean also open borders through which terror organisations can penetrate Israeli territory and commit terror acts," Nahshon says.

But lawyers fighting against the Third Country policy in Israel's Supreme Court argue that the country is in breach of its obligations under the UN Refugee Convention.

"[Migrants] are stigmatised as 'infiltrators' and then have their asylum application adjudicated in sort of a conveyor-belt system which rejects everyone," says one of the lawyers, Anat Ben-Dor.

"And then the whole idea of asking them to give their 'voluntary' consent to something they do not know because this is a secret arrangement... Of course this is not voluntary because you are using the threat of putting them indefinitely in prison if they refuse to go.

Image caption Graffiti at the Holot detention centre

"And then when they land in one of those two countries the lack of proper monitoring cannot really secure, in the necessary certainty, that those people would not end up either without [legal] status, or in prison, or - worst of all - being returned to places where they would face danger."

Sigal Rozen, from the Israeli human rights group Hotline for Refugees and Migrants, says that the failure by Israel to guarantee the migrants' security in Rwanda and Uganda means they are forced to risk their lives elsewhere.

"Some of them continue to South Sudan, others to Kenya, to Ethiopia, and many end up in Europe after they take the route through Libya and Italy. Unfortunately many others die on the way and we never hear from them again," she says.

There's a joke among the migrants, she says, that the Israeli government's departing "gift" of $3,500 is just enough money to get to Europe.

But the Israeli government is adamant that it's acting within the framework of international law and is offering a fair deal to the migrants.

But in Tesfay's opinion, he did not get a fair deal.

"The Israeli authority - it's not what they promised. I have no safety - I have no protection at all," he says.

The risk is that Adam and the other residents of Holot will experience exactly the same thing when they arrive in Africa.

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