Students in Catalonia began an indefinite strike on Tuesday against the imprisonment of political leaders and police conduct during the protests that followed the sentences.

Yet, the students taking part in the strike are also calling for the option to choose a single end-of-term exam rather than being subject to a continual assessment grading system.

The strike began early on Tuesday morning with a number of protest actions carried out by some students from different Catalan universities.

Motorway and classrooms blocked

Students from Barcelona's Autonomous University (UAB) blocked southerly traffic for a time on the AP-7 and B-30 motorways around 11am.

Meanwhile, students spent the night in preparation for the strike on campuses of Barcelona's Pompeu Fabra University (UPF) and Catalonia's Polytechnic University (UPC).

The UPF was the university that was most affected by the strike, where groups of students formed pickets to prevent students not participating in the stoppage from going to class.

After moments of tension between opposing groups, the university authorities advised students not to go to class until the situation had returned to normal.

There were similar incidents in the UPC's engineering faculty in the city of Manresa, where picketing students also blocked access to classrooms.

However, attendance to classes in the University of Barcelona (UB) was fairly normal, and the strike was only noted in classes in the Fine Arts faculty.

Universities to debate more flexible evaluation

Most universities responded to the students' demands for a single end-of-term exam by announcing the possibility of offering alternative systems of evaluation.

The UPF offered a single evaluation for those students who demand it, while the UAB and UPC said they would debate the possibility of introducing the option this week.

Meanwhile, nine UB faculties reached agreement to make evaluation more flexible, while Girona University (UdG) said the matter will be discussed at a special meeting on Thursday.