Separatist campaigners targeted Catalonia’s transportation networks in protests held to mark the anniversary of an illegal independence referendum held a year ago.

Protesters blocked the AP-7 highway at Vandellos, a town 140 kilometers (87 miles) south of the regional capital Barcelona, the Catalan Traffic Service said on its Twitter account Monday. The high speed train service from Figueres to Barcelona was interrupted after protesters blockaded the line at Girona, rail company Renfe said on Twitter. Traffic has also been cut in some of the main avenues of Barcelona, local police said.

Among other incidents, a group of more than a hundred separatists forced their way into the central government office in Girona and replaced the Spanish flag with a pro-independence banner, news agency Europa Press reported.

Separatists groups are holding protests to mark the anniversary of an attempt to hold a referendum on Catalan independence—and violent police action to prevent it—on Oct. 1 2017. The new Socialist government of Pedro Sanchez is trying to reach out to Catalan public opinion still bitter over last year’s events, a task made more difficult by the fact that nine separatist leaders remain in jail.

Separatists should keep up their pressure to push for a Catalan republic, said regional President Joaquim Torra, speaking in Sant Julia de Ramis, a town that witnessed tough police action last year to prevent voting in the referendum from taking place.

Carles Puigdemont, the former Catalan president who led the bid to secede and is now living in Brussels to avoid arrest in Spain, said last year’s vote was the “start of a new irreversible era.” “We won’t be turned away from the only possible way to live in a full democracy: the achievement of the Catalan republic,” he said in a statement on Youtube.

A march in support of Spanish police led to rioting in Barcelona on Saturday as tensions rose ahead of Monday’s anniversary. Spain’s Minister for Territorial Policy Meritxell Batet said in an interview with Bloomberg last month that separatist leaders must make a “brave” move to help heal wounds in the region’s divided society.

“There is nothing to celebrate about Oct. 1—it is a sad day to remember,” Isabel Celaa, the spokeswoman for the Spanish government, told Cadena Ser radio station in an interview Monday. “That day showed as never before the fracture of the Catalan society.”

Since taking power in June, Sanchez has taken a more conciliatory approach than his predecessor Mariano Rajoy but has had little room to maneuver with many people in the rest of Spain still outraged at the prospect of any concessions to the separatists. Last year’s referendum was declared illegal by Spain’s constitutional court.