Acting on a European arrest warrant, police in Germany have detained Catalonia’s ex-leader Carles Puigdemont. Wanted in Spain for sedition and rebellion, he will appear before a German judge on March 26 – a formality to confirm his identity.

Puigdemont’s lawyer said police apprehended him while crossing from Denmark on the way to Belgium.

As reported by the BBC, Puigdemont’s supporters gathered in Barcelona to protest against his arrest. The charges he faces in Spain could result in 30 years in prison.

They chanted “Freedom for the political prisoners” and “This Europe is shameful!” as they headed to the offices of the European Commission.

During his self-imposed exile following the resulting crisis, Puigdemont told Belgian TV he was not hiding from “real justice” but from the “clearly politicised” Spanish legal system.

In a separate report, the Financial Times noted that Puigdemont’s detention threatens to escalate already fierce tensions in Catalonia.

Franziska Brantner, the European affairs spokeswoman for the Greens said Puigdemont’s fate had to be decided by the court but added: “This case shows that it is high time to find a political solution in Spain.”