BERLIN — Authorities in Germany arrested former Catalan president Carles Puigdemont on Sunday after he crossed into the country from Denmark, setting up a possible extradition of the fugitive separatist leader to Spain.
Puigdemont’s lawyer said his client had been taken to a police station. German police confirmed that Puigdemont had been arrested at 11:19 a.m. Sunday by highway patrol officers in Schleswig-Holstein, a state that borders Denmark.
Prosecutors said a court would decide at a procedural hearing Monday whether to keep Puigdemont in custody pending a Spanish extradition request.
Authorities had been tipped off that Puigdemont would be entering Germany, and multiple German media outlets reported that Spanish intelligence had been used to snare the Catalan nationalist.
In Barcelona, thousands of proindependence Catalans gathered to protest the arrest, leading to clashes with police, the Associated Press reported. Protesters also turned out in the northern city of Girona, where Puigdemont was mayor before he became regional president in 2016.
The arrest marked the latest in a series of maneuvers that have left Catalonia’s independence movement with few leaders who are not either being held or sought as fugitives.
Puigdemont is wanted in Spain on charges of rebellion and sedition arising from his role in organizing an October referendum on Catalan independence. If convicted, he could face as many as 30 years in prison.
The Catalan leader has been living in self-imposed exile in Belgium since he fled Spain five months ago amid the uproar over the referendum.
Separatists won that vote, and Puigdemont’s government declared independence. But the Spanish government deemed the ballot unconstitutional and imposed direct rule.
Spain had reactivated an international arrest warrant for Puigdemont on Friday. At the time, he was in Finland. But his attorney, Jaume Alonso-Cuevillas, said Saturday that Puigdemont had left Finland and was en route to Belgium.
Puigdemont’s attorney said that German police have been following proper procedures since the arrest and that his client had intended upon his return to Brussels to ‘‘put himself, as always, at the disposal of the Belgian justice system.’’
The detention comes at a tense moment in Catalonia. Separatists hold a majority in the regional Parliament following elections in December. But they have not been able to form a government and have abandoned plans to name a new president after the arrest of their latest candidate, Jordi Turull.
Puigdemont had sought to reclaim the presidency for himself but abandoned that bid on March 1, announcing in a 13-minute video that he had come to the decision with ‘‘the greatest sadness.’’
But he also said he would set up a foundation that had the makings of a government in exile.
‘‘I will not throw in the towel. I will not quit. I will not give up in the face of the illegitimate behavior of those who lost at the ballot box,’’ he said.
That message was in contrast to the one he had communicated privately to a colleague in messages that were captured by a TV camera and that acknowledged the Spanish government’s crackdown ‘‘has won.’’
‘‘I guess that you’ve realized that this is over,’’ reads one of the messages.
On Friday, Spain issued five other international arrest warrants, including for four former Catalan ministers also believed to be in Belgium.
The warrants came as the Spanish Supreme Court ruled that 25 Catalan leaders should face charges for rebellion, sedition, or embezzlement.
Thousands answered the call by a pro-independence grass-roots group to protest in Barcelona and other cities hours after Puigdemont was detained. Catalonia’s regional transit service said protesters cut off traffic on four highways, the AP reported.
In Barcelona, police in riot gear struck demonstrators with batons as they tried to push back a large crowd that tried to advance on the office of the Spanish government’s representative in Catalonia.
In Scotland, police said the lawyer of another fugitive former member of Catalonia’s government has contacted officers and is preparing for the politician to be handed over to authorities.
A European warrant was issued for Clara Ponsati, Catalonia’s former education chief, who fled from Spain along with Puigdemont and other Catalan leaders in October.