By Dominic Bailey
The European Union is seen as the land of opportunity by many living in desperate poverty in Africa.
Immigrants are trying to cross before the fence work is completed
On a clear day you can see Spain across the water from Morocco and many have drowned trying to cross the narrow straits in rubber dinghies, old boats or on inflatable inner tubes.
But the enclaves of Ceuta and Melilla - Spanish territory clinging to the Moroccan coast - offer an alternative entry point. Across the double fences lies Europe and the dream of a better life.
There are thought to be more than a million illegal immigrants in Spain.
Last year, Spanish authorities detained more than 15,674. But
those who arrive without identity papers are often released as Spanish immigration laws do not allow police to expel people if they cannot prove their identity or nationality within 40 days.
But faced with increasing numbers trying to cross the border fences Spain has revived a 1992 accord with Morocco to allow expulsions of illegal entrants back to Morocco, even if they are of different nationalities.
This year alone more than 12,000 have attempted to enter Melilla in the hope of getting that foothold in Spain. Some in recent weeks have died trying.
Human rights groups are concerned that Spanish and Moroccan governments' efforts to control these crossings are going too far and putting immigrants' lives at risk.
Alarmed by the latest mass crossing attempt, the Spanish government has sent army reinforcements to the border police, who work in tandem with Moroccan guards on the other side.
The double fence barrier that marks the perimeter is being raised from three to six metres tall and should be completed by February 2006. An extra perimeter barrier mesh of steel wires, which the government says will cause less injuries, is also due to be built around the existing fences.
Sensors will also alert guards to possible immigrant invasions.
Secretary of State for Security Antonio Camacho insists Spain is following its policy of rigorous control of illegal immigration while supporting immigrants who arrive legally.
After visiting Melilla and Ceuta this week he said both enclaves were facing "a grave human and social problem".
A government representative in Melilla said the enclave was "saturated" with immigrants.
Earlier this week Melilla border police faced 1,000 people trying to cross the fences. They managed to repel most but around 300 got through.
Most then report to the police station for processing. The government spokesman said it was the authorities' task to try to identify them - either from papers or by taking fingerprints.
He said the majority do not usually ask for asylum. They are then sent to temporary holding centres (Ceti) to await expulsion or repatriation.
Under a bilateral agreement, Spain can send back Moroccan illegal immigrants, but it lacks repatriation agreements with many other African countries.
Since April, the authorities have started a programme of transferring immigrants from the centres in Ceuta and Melilla to the Spanish mainland to relieve the pressure on living conditions
The Ceti in Melilla has around 1,150 people, but it was built for 480.
Melilla's temporary holding centre has been overwhelmed
Some are taken to Spain with the right papers, while others are transferred to internment centres before expulsion. Reports say some are released when they reach the mainland after being handed the expulsion order which the authorities cannot carry out.
Enrique Santiago, secretary general of the Spanish organisation CEAR that works with refugees, says the crossings are nothing new. Only now, he says, they are becoming more frequent and more desperate.
"The Moroccan government is working with the Spanish on immigration control and has started to use methods which fail to respect national accords in relation to human rights," he said.
"This has led to a systematic harassment of the camps where sub-Saharan immigrants hide out on the other side of the border."
Mr Santiago said this had led to a humanitarian crisis in the African encampments. Both these factors have pushed these people to try to cross the border out of desperation, he said.
News about the border fence being raised from three to six metres has prompted more people to try to cross before the work is completed.
Furthermore, Mr Santiago fears that increasing the height of the fence will not stop people trying to cross it - only add to the tragedy.
"The crossing in Ceuta last night was at part of the border which was already six metres high," he said. "The only thing this has done is cause two deaths caused by falling six metres. The risk increases, but it is not going to stop the crossings."
He also echoed concerns raised by Amnesty International in a report published earlier this year that the sub-Saharans who manage to get to Ceuta-Melilla are not getting the necessary legal support before being sent back.
"They are not delinquents, they are not committing a crime," he said.
"They are trying to abandon their misery and get to countries which supposedly have better living conditions."