Amid ongoing protests in Catalan, Spanish Prime Minister Pedro Sanchez said on Friday that his government was working to ensure that laws were “upheld inside and outside” Spain’s borders.

Sanchez spoke to the violent protesters in connection with the protests that took place in the Catalan region of Spain over the past four days.

“The law is clear and those who commit an illegal act have to answer for it,” Sanchez said on the day that saw former Catalan leader Carles Puigdemont turned himself in to the Belgian authorities after Spain reissued an international arrest warrant for him for his role in the 2017 referendum and the subsequent unilateral declaration of independence in the Catalan region.

The past four days have now seen over 100 people arrested and over 200 police officers injured in clashes in Barcelona between security forces and small but well-organized and violent groups of demonstrators.

Sanchez insisted that his acting government will not tolerate violence, saying that “there will be no room for impunity in the face of the violence we have seen in Catalonia.”

“It is important to vindicate a proportional response, the law means we could apply extraordinary measures, but it is important to have social legitimacy and reflecting on our actions will help calm things down and redirect the situation,” Sanchez added.

PM Sanchez also spoke to the media in Brussels on the same day that a strike was held in Catalonia to protest against the prison sentences given to 13 Catalan political and social leaders on Monday for their roles in the independence referendum held in the region in 2017, which was declared illegal by the Spanish Constitutional Court.

The strike has so far caused 57 flights to be cancelled from Barcelona’s El Prat airport, and cruise ships had to be turned away from the Port of Barcelona, which was closed due to the strike along with the port of nearby Tarragona.

Earlier on Thursday, Catalonia’s separatist leader has vowed a new vote on secession from Spain within two years.

Addressing the regional parliament, Catalan President Quim Torra denounced any violent tactics used by the demonstrators, calling the separatist cause a peaceful one. But he also pushed the case for forging ahead with the stalled secessionist drive in a region that has its own language, flag and legislature.

“If all parties and groups make it possible, we have to be able to finish this legislative term by validating independence”, Tora added.

Earlier on Monday, the Spanish Supreme Court sentenced nine Catalan separatist leaders to between nine and 13 years for sedition and misuse of public funds for their role in the 2017 independence referendum considered illegal by Madrid.

Vice President of the Catalan Parliament Oriol Junqueras was sentenced to 13 years prison for sedition and misuse of public funds, while politicians Raul Romeva, Dolors Bassa and activist Jordi Turull have all been handed a 12-year sentence.

In 2017, police and protesters clashed when Catalonia’s pro-independence leaders went ahead with a referendum ruled illegal by Spain’s constitutional court.

In September, a march in Barcelona in support of Catalonia’s independence from Spain drew crowds of about 600,000 people – one of the lowest turnouts in the eight-year history of the annual rally.

(With inputs from agency)