Police arrested 10 young people in Spain linked to the “Blocus” movement over alleged plans to unleash mass looting and street violence for Halloween. The operation, coordinated by the Policía Nacional, the Guardia Civil and the Mossos d’Esquadra, unfolded in the 24 hours before Halloween, with four suspects confirmed as minors. Investigators say the alleged coordination was run through Telegram channels controlled by the movement, with arrests starting in Valencia. In Picanya, the Guardia Civil detained a 20-year-old accused of being the suspected founder, responsible and driving force behind Blocus in Spain, and said he managed the “main rooms” on Telegram used to coordinate the unrest. Two more arrests followed in the region. In Valencia, a 17-year-old was detained for allegedly administering groups that grew to around 400 users and for allegedly urging fires to distract patrols. In Alfafar, a 18-year-old was arrested for allegedly instigating the use and manufacture of Molotov cocktails to spark chaos. Catalonia saw further arrests linked to the alleged scheme. After the October 24 incidents in the region, which left 133 arrests, 23 shops looted, 33 fires and 14 officers injured, the Mossos d’Esquadra detained three more people. In Sant Sadurní d’Anoia, a 17-year-old was accused of spreading links to evade police, providing instructions to avoid tracking, and sharing guidance and specific store targets for looting. In Barcelona, a 18-year-old was arrested as an alleged instigator and driver of the violent actions. In Bellmunt d’Urgell, Lleida, a 16-year-old was detained for allegedly running messaging channels used to call for sabotage and attacks on police scheduled for October 31. Police action extended to other regions. In Tenerife, the Guardia Civil arrested two suspected leaders, including a 16-year-old, and described a method allegedly imported from France using encrypted communication tools and tactical maps. In Bilbao, the Policía Nacional detained a 20-year-old accused of running an Instagram account linked to Blocus, calling for a violent mobilization in the city center on October 31. In Málaga, another 20-year-old was arrested for alleged involvement in messaging channels urging looting in Málaga city, Fuengirola and Marbella during Halloween. Authorities said they did not identify an extremist ideology or organization behind Blocus so far, describing it instead as a possible “mirror effect” of similar unrest in France amplified by social media dynamics. The investigation remains open, and police said they do not rule out further arrests.