A 23-year-old man has been arrested in Morocco, in a joint anti-terrorist operation with Spain, over an alleged plan to attack Spain’s Holy Week festivities.

The suspect’s name is Zouhair el Bouhdidi and he is a student at the University of Seville. According to police sources in Spain, the young man was preparing an imminent attack against the processions of Holy Week in Seville, one of the most important events of the Catholic calendar. According to the newspaper El Confidencial, el Bouhdidi has already confessed to the Moroccan police his plans to commit a “large-scale massacre” in the Andalusian city. The Spanish secret services had reportedly been following him for several weeks.

Holy Week in Seville is a celebration declared as a Fiesta of International Tourist Interest. Nearly 70 brotherhoods come out in procession with wooden sculptures depicting scenes of the Passion of Christ between Palm Sunday and Easter Sunday. The procession called La Madrugada—on the night of Thursday into Good Friday—brings together hundreds of thousands of people from all over the world, crowded through the narrow streets of Seville.

El Bouhdidi allegedly intended to attempt the attack this week in Seville with a homemade explosive known as “the mother of Satan.” It is the same type of explosive that terrorists prepared in the attack on Barcelona ​​in August of 2017, and in the attack on the Bataclan in Paris in November 2015.

Spanish police are now investigating the home of the alleged jihadist. El Bouhdidi lives in Su Eminencia (‘His Eminence’), a humble neighborhood of Seville. Neighbors say that he had never caused problems, although he did not really associate with others, and that the blinds in his house used to be closed. His recent trip to Morocco has been interpreted by the police as a possible farewell visit to his family.

Spain’s CNI (National Intelligence Center) is investigating whether el Bouhdidi was inspired by, or connected to, a video that the Islamic State published in recent days, in which they threatened to attack the religious celebrations of Holy Week in Spain. The video has been broadcast by several jihadist groups on Telegram and includes images of the attacks in Barcelona and crowds of people participating in the processions of Holy Week in Spain.

The threats against Spain have been spread on social networks by the Muntasir Media Foundation, which is responsible for propagating jihadist messages and which had already threatened Spain last December. The recent video encouraged attacks against Holy Week in Andalusia, the region of Spain that corresponds to Al Andalus, which was Muslim territory before the Reconquest. Recovering Al Andalus is an old obsession for jihadists and often appears in many of their propaganda messages.

The thwarted attack would have taken place only 11 days before the general elections in Spain. In 2004, three days before the general elections, the Madrid bombings ripped through the heart of Spain’s capital, leaving 193 dead and more than 2,000 injured. Since then, the Spanish police have doubled up on terrorism protection in the days before each major election.

A suicide attack in Holy Week in Seville would have certainly claimed many victims, in addition to causing a huge international media panic. On the other hand, one of the great dangers of La Madrugada—the most famous procession—are the stampedes: In 2017, more than a hundred people were wounded after a stampede was set off by eight mischief-makers, who had been recruited through social networks for a dangerous prank.

One of the issues on the table in the electoral campaign is the possibility of tightening laws and borders to prevent the entry of jihadists, potentially hiding among other immigrants, into Spain. This is one of the proposals of the far-right party VOX, which has been growing in popularity in Spain according to all the polls. The president of Spain and main socialist candidate are both against hardening the laws. In recent weeks the controversy over the entry of jihadists in Spain has been present in all media and is generating polarized positions among the Spanish.