Over 700 refugees from the Middle East and Africa are feared dead in a pair of catastrophic shipwrecks in the Mediterranean Sea over the past week, the world’s main international migration agency reported Monday.

This tragic loss of life is directly bound up with the series of military interventions carried out by US imperialism and its allies, which have plunged the Middle East and much of Africa into chaos, turning millions into homeless refugees.

The worst of these maritime disasters became known over the weekend from the accounts of two Palestinian refugees who were pulled from the sea after clinging to flotation devices for a day and a half. They reported that their ship, carrying some 500 migrants from the Palestinian territories, Syria, Egypt and Sudan, had gone down last Wednesday after a violent confrontation with human traffickers who deliberately rammed the vessel.

Meanwhile, a boat carrying over 250 other refugees capsized off the coast of Libya on Sunday, with only 36 survivors rescued from the sea. The rest of the passengers are believed to have drowned.

The confrontation that led to the 500 migrant deaths reportedly erupted after the traffickers attempted to force the refugees to abandon the ship that they had embarked upon from the Egyptian port of Damietta for an even less seaworthy boat off the coast of Malta. When the migrants resisted, their ship was rammed and sunk.

The Palestinians were rescued by a Panamanian-registered container ship, while seven other survivors were pulled from the sea by the Maltese navy and other vessels. The same Panamanian-flagged ship that rescued the Palestinians managed to save another 380 refugees whose boat had also sunk in the Mediterranean over the past week.

“If this story, which the police are investigating, should be confirmed, it would be the gravest case of recent years, since it was not an accident, but a mass murder perpetrated by criminals without scruples or respect for human life,” the International Organization for Migration (IOM) said in a statement Monday.

The IOM, however, did not limit itself to denouncing the direct perpetrators of this crime. The agency’s statement added: “The only way to neutralize these criminal organizations is to start opening legal entry channels to Europe for all people, men, women and children, who flee from their countries in search of protection.”

The “Fortress Europe” policy pursued by the member states of the European Union has been aimed at a diametrically opposed objective—namely, the sealing off of the continent from the flood of refugees.

In a statement on the disaster, Amnesty International denounced the EU’s policies as directly responsible for the tragic mass deaths. “The response of EU member states to the refugee crises in the Middle East and North Africa has been shameful,” John Dalhuisen, Amnesty International’s Europe and Central Asia director, said in a statement released Monday.

He added, “European leaders want to prevent people from reaching Europe at any cost, forcing desperate people to take more hazardous routes.”

“It is without any doubt the deadliest weekend ever in the Mediterranean,” Carlotta Sami, a spokeswoman for the Office of the United Nations High Commissioner for Refugees, said Monday. She added that the UN agency was seeking to confirm as many as five shipwrecks in the region in just the past several days.

These latest disasters have already made 2014 the deadliest year in terms of migrant deaths in the Mediterranean, which now approach 3,000, more than four times the number of refugees who lost their lives crossing the sea over all of last year. These figures, which reflect only deaths confirmed by the authorities, undoubtedly represent a considerable underestimation of the real human toll.

The leap in the number of migrants seeking to make the dangerous crossing is directly bound up with the multiple crises unleashed by imperialist interventions in the region.

The sectarian civil war instigated by Washington and its allies in pursuit of regime change in Syria has turned over 3 million Syrians into refugees and another 6.5 million into internally displaced persons.

Millions more have been displaced by the descent of Iraq into civil war in the wake of nearly a decade of US occupation. Libya, from which many of the refugee boats embark, has disintegrated in the aftermath of the 2011 US-NATO war to topple the regime of Muammar Gaddafi, with bloody fighting between rival militias forcing both African refugees in the country and Libyans themselves to flee for their lives.

During the first 10 months of fiscal year 2014, as millions more joined the ranks of Syria’s refugees and displaced persons, Washington admitted a grand total of 63 Syrian refugees into the United States. The European Union has done little better in terms of providing refuge to those fleeing the region’s wars.

There is no doubt that the launching of another major war in the region by the US and its allies under the pretext of combating the Islamic State of Iraq and Syria (ISIS) will only deepen the humanitarian catastrophe, leading to an even greater flow of refugees.

The worst previous tragedy involving migrants attempting to reach Europe by crossing the Mediterranean took place in October 2013 near the Italian island of Lampedusa off the coast of Sicily. The sinking of a refugee boat there claimed the lives of nearly 400 refugees, in their overwhelming majority from Africa.

In response, Italy mounted an operation dubbed Mare Nostrum (Our Sea), a phrase previously employed by the fascist regime of Benito Mussolini to promote Italy’s imperial ambitions. While touted as a humanitarian search-and-rescue mission, the main aim of this militarized naval operation has been to interdict and detain refugees, many of whom are summarily deported back to their home country or to Libya, where they face imprisonment and torture in detention camps.

This Italian operation is slated to be replaced by the end of November by an interdiction program dubbed Frontex Plus, to be run by the EU’s border-control agency Frontex.

Frontex has already participated in the Italian program by providing intelligence gleaned from satellites and drones operated by EUROSUR, the EU’s border surveillance system. This allows the speedy interception of refugee boats, which in many cases are forced to turn back to Libya, or their interdiction, with their passengers relegated to camps on the Italian mainland awaiting immigration processing that most often ends in deportation.

The objectives of the Frontex operation were spelled out earlier this year in new Sea Borders Regulations instituted by the European Parliament’s Committee on Civil Liberties, Justice and Home Affairs. The regulations grant the border agency the power to block and forcibly send back boats carrying refugees. They constitute a violation of the so-called non-refoulement principle embodied in the Geneva Refugee Convention, which prohibits the return of refugees to countries where they face the threat of human rights abuses.