Among the targets of the rapper's controversial tweets were the police, which he described as "mercenaries of s***," and the monarchy.
Police have arrested a rapper sentenced to a controversial prison term in north-eastern Spain on Tuesday morning for tweets attacking the monarchy and the police, according to Spanish media.
"They will never make us bend, despite all the repression," said rapper Pablo Hasel, fist raised as he was escorted by the police. He had barricaded himself in a building at the University of Lleida in Catalonia on Monday with supporters to try to prevent his arrest.
The operation was launched at 6.30 am CET by agents of the Mossos d'Esquadra who took supporters of Hasel out of the university one by one.
"We entered the university and began the operation to enforce the judicial decision" on his arrest, a spokesman for the Catalan regional police told AFP.
"There are some barricades that have been prepared" to prevent police access "but no serious incidents have taken place for the moment," added the police spokesman.
The rapper had until Friday night to voluntarily go to prison and begin serving his nine-month sentence for tweets in which he described the Spanish police as "mercenaries of s***," accused them of torture and murder, and also attacked the Spanish monarchy.
"They will have to come and kidnap me and that will also serve to portray the state under its true face, that of a false democracy," he told AFP on Friday.
Several tense demonstrations in support of the rapper have taken place in Madrid and Barcelona in recent weeks, while more than 200 personalities from the Spanish-speaking cultural world, including director Pedro Almodóvar and actor Javier Bardem, signed a petition in his favour.
The affair has become a real thorn in the side of the left-wing government and especially its main component, the Socialist Party (PSOE). On the defensive, the government promised "a reform" last week so that "verbal excesses committed in the framework of artistic, cultural or intellectual events" would no longer come under criminal law and or result in prison sentences.