Updated at 12:40 a.m. ET on Monday
Carles Puigdemont, who led Catalonia's independence push before slipping into Belgium to evade rebellion charges, was detained by German police Sunday as he crossed into that country from Denmark, according to a tweet from his lawyer.
Jaume Alonso-Cuevillas said Catalonia's former president was on his way back to Belgium from Finland, where he had been meeting with lawmakers, when police stopped him on a European arrest warrant.
Puigdemont faces up to 30 years prison time in Spain for heading an illegal independence referendum in October.
Violence erupted during the vote, "Horrible scenes," as NPR's Lauren Frayer reported from Barcelona at the time, "Police dragging voters out of polling stations, some by the hair."
His arrest Sunday caps a tense weekend in Catalonia after Spain's Supreme Court ruled Friday that 25 Catalan leaders should stand trial on secession-related charges, carrying sentences of up to three decades behind bars.
Five politicians who responded to a court summons found themselves jailed, reports The New York Times.
As many as 55,000 people took to the streets in Catalonia, according to Spanish news agency Efe, in protests that carried on through the weekend.
In central Barcelona, protesters chanted "Freedom for political prisoners!" There were smaller protests reported in Girona, where Puigdemont had been mayor. Tarragona and Lleida also saw protests, according to the BBC.
Dozens of people were reportedly injured in clashes with police.
The judge also issued a new international arrest warrant for Puigdemont Friday, making him a wanted man across Europe once again, after his prior extradition order was lifted in December. (A national arrest warrant has been in effect since November, meaning Puigdemont has not been free to step foot back on Spanish soil.)
Puigdemont was in Finland Friday when he learned Finnish police could be preparing to arrest him.
Finnish member of Parliament Mikko Kärnä, who had been meeting with Puigdemont, said Saturday that the deposed leader opted to leave the country for Belgium rather than turn himself over to Finnish police.
A Spanish police official told The Associated Press that its intelligence services worked with German police to orchestrate Puigdemont's arrest.
Like Puigdemont, other politicians facing charges have left Spain to live in self-exile.
Catalan parliament member and lawyer Marta Rovira fled to Switzerland rather than appear in court Friday, according to the Times. She said in an open letter Friday, "Exile will be a tough road, but it is the only way I have to recover my political voice."
Friday's indictment is another major snag for Catalonia's long-running secessionist movement, as much of its political elite is facing decades behind bars.
It is up to Germany as to whether Puigdemont will be extradited.
NPR's Lauren Frayer contributed to this report