OVIEDO, Spain

Police and protestors clashed Tuesday night at free speech rallies in support of Spanish rapper Pablo Hasel, who was arrested earlier in the day after being sentenced to prison over politically-charged tweets and song lyrics.

Hasel was charged with glorifying terrorism and insulting the monarchy and state institutions.

Dozens of protests were called across Spain, some of which quickly escalated into violence. Eight people were arrested in the city of Lleida and three in the province of Barcelona, Catalan police said.

In the cities of Barcelona and Girona, police fired rubber bullets at protestors who were throwing objects at them and lighting fires. Local media say seven protestors were injured, one woman seriously in the eye.

In Barcelona, rioting broke out with protestors reportedly looting a bank and breaking the windows of a police station. Police also charged at protestors in Valencia.

In Lleida, the rapper’s hometown, some protestors vandalized political party and government buildings as more clashes with police ensued.

The rapper, whose real name is Pablo Rivadulla, had until last Friday to voluntarily surrender to authorities and serve a nine-month prison sentence.

But he refused to turn himself in to draw attention to what he, organizations such as Amnesty International and even members of the Spanish government called the “injustices” of his sentence.

Some of the tweets that landed him jail time included one calling former Spanish King Juan Carlos (currently exiled in Abu Dhabi amid corruption allegations) a thief and mafia boss and another accusing Spanish police of torture and impunity.

More than 200 Spanish artists including film director Pedro Almodovar and actor Javier Bardem have signed a petition backing him and calling on the government to reform Spain’s free speech laws.

Commentators pointed out the irony of Spain’s free speech laws after around 300 people attended a sanctioned Neo-Nazi rally in Madrid over the weekend. There, one of the speakers was recorded saying: “The enemy will always be the same, although with different masks: the Jew…The Jew is the culprit.”

After Rivadulla’s arrest Tuesday, Madrid authorities said they launched a probe, heeding calls from several major organizations to investigate the event.

Rivadulla joins a growing list of people to have landed similar charges over tweets or artistic expression.

The European Court of Human Rights has ruled against Spain on three occasions for its law making it illegal to insult the monarchy. According to the court, it is contrary to freedom of expression, which is enshrined in Article 10 of the European Convention on Human Rights.

Last week, members of Spain’s left-wing coalition government said they will review laws around “crimes of expression.”