Madrid, Spain—The Spanish Government decides to mass-expel African immigrants.

Over 166 Sub-Saharan Africans will be deported from Spain after they breached a barbed wire fence and assaulted immigration guards in the autonomous city of Ceuta.

Spain and Morocco have signed an extradition agreement that enables the Spanish government to proceed to such deportations if it judges it appropriate. Until now the agreement had rarely been triggered.

The incident happened on July 26, when more than 600 immigrants attacked the six-meter-high security fence that guards Spanish territory. They lobbed Molotov cocktails and feces at the Spanish Civil Guard police force, resulting in several serious injuries.  Most alarmingly, however, is that the assaulters were highly organized: some groups busied the Spanish law-enforcement officers whilst their comrades breached the fence with improvised cutting tools allowing hundreds to slip through.

This incident will surely rattle Spanish politics.

Earlier in the summer, and in an unexpected turn of events, conservative Prime Minister Mariano Rajoy was forced to resign. Pedro Sanchez, the new socialist PM, promised a more tolerant immigration policy.  But now he is pushed into a reversal, an event that has made him vulnerable to attack from the Spanish left. The populist-leftist Unidos Podemos and the Catalan and Basque nationalists accuse the government of human rights violations.

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The opposition, on the other hand, accuses him of being too liberal.  According to the leader of the opposition, Pablo Casado, immigration has tripled since the new socialist government came into office.

Sanchez now faces a dilemma: his minority government depends on the continuous support of left-leaning political parties, but he also can’t ignore the security threats posed by illegal immigration.

Adding to his worries are the threats of many Civil Guard officers, who have threatened to resign if their undermanned and underfunded units don’t receive more support from the government.

“We have to start removing some of these people and prevent more from getting here,” said a retired Civil Guard general who advises the interior ministry in border-control issues.

Going against the current, Spain has granted asylum to most migrants who manage to reach Spanish soil. Indeed, Spain has one the most liberal immigration policies in Europe. And this comes in a time of overwhelming immigration from Africa and the Middle-East.

After reaching EU soil, mostly by sea, migrants seeking asylum are quartered in temporary camps. The conditions of these camps vary by the country and region. Governments and NGOs then process their applications for asylum and EU free-movement passes. Nearly all migrants seek entry to a northern European nation, with Germany, Sweden, and the Netherlands being among their top choices.  Economic prospects are much better in north European countries, who are frustrated by the influx of immigrants within their borders and accuse their southern neighbours of lax border-control.