By Pascale Harter
Every summer thousands of illegal immigrants from sub-Saharan Africa make their way to Morocco in order to cross the narrow Strait of Gibraltar on their way to a new life in Western Europe.
Sarah crossed over to Spain one month ago. Heavily pregnant, she set off at night on an over-crowded boat and spent 13 hours on a rough sea.
"It was all very upsetting. I don't remember much before they rescued us because I was not feeling myself.
"I was so cold and alone - A pregnant woman alone!" Sarah said.
The next day after arriving in Spain, Sarah gave birth to a baby girl, whom she named Success.
I asked Sarah what made her spend one year travelling across Africa from her native Nigeria, and risk her life and her unborn child's.
She replied simply that she wanted to experience Europe and see it for herself.
Sarah says once she has her papers she will find work and settle down.
The journey, often made on crowded and badly-maintained boats in the dead of the night, is a dangerous one.
The Spanish Guardia Civil (Civil Guard) which patrols the coast for immigrants, says some have even tried to swim across or paddle on surfboards, tyres and pedallos hired by the hour on Morocco's tourist beaches.
Once these immigrants were desperate men and women, risking life and limb in order to flee war and famine.
About 2,000 African immigrants a year attempt to reach Tarifa from Morocco
But now, say the Red Cross, and the Spanish Civil Guard, the vast majority are middle class.
They are overwhelmingly women, frequently pregnant or with babies, who say they are searching for greater opportunities in Europe.
Captain Jose Gil Ochoa of the Civil Guard in the Spanish tourist resort Tarifa, says at one point 300 illegal immigrants a day were crossing from Africa.
Now, with the coastline surveyed by night-vision cameras, he says the number is much lower, about 2,000 a year.
But one of his staff told me privately that they had already caught 8,000 attempting to cross so far this year, an estimate echoed by the Red Cross.
The sub-Saharan immigrants who get caught are the lucky ones - they have made the journey safely and are allowed to stay.
But many do not survive and the bodies of those seeking a new life in Europe wash up dead on the tourist beaches of Southern Spain instead, says Captain Ochoa.
Sarah is one of 20 Nigerian women staying in the Catholic Mission of the Cruz Blanca (White Cross) in the Spanish port of Algeciras.
Sarah is not her real name. Like the other women staying at the mission, Sarah was not keen to tell her story.
She told me that a Mafia trafficking illegal immigrants was operating in Morocco, but that she did not know who they were.
She said other people paid for the "ticket" to get her across, but she doesn't know how much.
Some of the Nigerian women put the price for an illegal night crossing on a rickety boat at $1,000.
A fee many of the women are later expected to work off.
Captain Ochoa of the Civil Guard says there is not much evidence of a Mafia in place.
He says the traffickers are often Moroccans, in worse circumstances than the sub-Saharan immigrants, trying to make a quick buck.
The Spanish Government is eager to play down the problem, to avoid being denounced as an easy point of entry into member states of the European Union.
But there are clear signs that a well-organised network of people traffickers are at work.
The Red Cross in Tarifa and inhabitants of the town say they regularly see groups of newly arrived sub-Saharan Africans walking to the motorway from where they are picked up by cars and trucks with Madrid number plates and taken on to the capital.
Success was born a day after her mum reached Europe
Father Isidoro who runs the Cruz Blanca mission in Algeciras has given food and accommodation to women like Sarah for more than 20 years.
He claims that there is a sophisticated and well-organised Nigerian Mafia trafficking women into Spain.
"They feed the women lies, filling their heads with talk of living well and finding good jobs in Europe," said Father Isidoro.
But Father Isidoro thinks the women often end up working as prostitutes.
"The Nigerian mafia men come from Madrid, covered in rings and gold, and they take them away in the car.
"They don't take the pregnant ones - but the ones who don't have a belly they take".
The police can't do anything because the women say it is their brother, Father Isidoro says.
Father Isidoro says the women will not speak out because they are afraid of reprisals against their family in Nigeria.
He has long been campaigning for work permits and the free entry of immigrants into Spain.
"It is the only way to get rid of the people-traffickers. But while they remain illegal, immigrants continue to risk their lives to get to Europe," says Father Isidoro.
The Civil Guard in Tarifa told me they had received information that 3,000 immigrants were waiting to make the crossing in the next few days.