It started with a whisper. A rumour, really. A claim that the border between Morocco and Spain’s North African territory of Ceuta had magically swung open. That if you just showed up, you could walk right into Europe.

By the time the dust settled, 72,000 people had poured into the tiny enclave——most of them swimming around a barrier in the Mediterranean Sea. At least 78 migrants drowned trying to make the crossing, according to Spanish authorities, with Morocco reporting another 11 deaths on its side of the border.

And the entire thing? It was fuelled by a wave of disinformation that generated 11 million views in the span of a few weeks.

The Rumour That Launched a Thousand Swims

The falsehood was simple, effective, and devastatingly viral: “The Ceuta border is open.” That message spread like wildfire across Facebook and WhatsApp, where experts say the bulk of the campaign unfolded. It didn’t matter that it wasn’t true. By the time fact-checkers could catch up, tens of thousands of people were already in the water.

The rumour was given a veneer of credibility by a real event: a July Supreme Court ruling that said irregular migrants intercepted at sea couldn’t be automatically returned to their country of origin. Within a day of that ruling, an Instagram post appeared claiming the border was effectively open. The message was “spread by accounts that were unidentifiable and had practically no interactions”—raising serious questions about the possible use of mass-diffusion algorithms.

A Deliberately Organised Operation?

An open-source investigation by technology company Golden Owl concluded “with a high degree of confidence” that the migrant rush “was a deliberately organised operation”. The European Democratic Party went further, accusing foreign actors of orchestrating the campaign “with the aim of destabilising Spain, undermining European migration policy and, ultimately, weakening Europe itself”.

Chema Gil, a security and intelligence analyst at the University of Murcia, tracked the online campaign and found it generated 11 million views from early July. Marcelino Madrigal, an expert in social media and security, told AFP there was “evidence that this was going to happen” and that the rumours, messages and groups that caused the crisis were mainly on Facebook and WhatsApp.

The Legal Reality Nobody Bothered to Read

The Supreme Court ruling never said what the rumours claimed it did. The text actually specifies that a different procedure applies only to those “intercepted on the high seas”—because those migrants don’t breach physical infrastructure. Human rights lawyer Laura Maria Medina Ferreras clarified that migrants “may be returned all the same”——the ruling just requires basic procedural guarantees.

But nuance doesn’t travel well on WhatsApp. And when you’re desperate enough to swim across a sea, you’re not exactly reading Supreme Court rulings.

The Fallout

Spain’s response has been swift and brutal. The government installed floating barriers off Ceuta’s Tarajal beach to prevent further sea crossings. The barrier, about 500 metres long, is designed to stop people from swimming around the border fence. Of the 72,000 who made it across, Spain says about 70,000 have been returned to Morocco.

But not everyone has gone back. Local officials estimate that between 3,000 and 5,000 migrants remain in Ceuta, living in squalid conditions with limited access to shelter, food, water and sanitation.

The New Calls Are Already Coming

Here’s the really worrying part. Social media expert Marcelino Madrigal has warned that “this isn’t over”. Fresh online posts are already calling for mass arrivals in August. Spanish authorities are monitoring social media closely, with new posts calling for another attempt on August 15.

Madrigal warned that social media platforms bear responsibility for not rebutting in time the content that encouraged last week’s rush, and said it was “very likely” a similar event would happen “in any part of the world”.

The Bottom Line

This wasn’t a spontaneous movement of desperate people. It was a carefully orchestrated campaign that weaponised hope——and turned it into a death sentence for 78 people. Social media platforms watched it happen in real time and did nothing until it was too late.

The border is now sealed. The barriers are up. The bodies have been recovered. But the next rumour is already spreading. And somewhere in the world, another group of desperate people is about to believe it.