MADRID -- A Spanish judge jailed Catalonia's top lawmaker Thursday in a rebellion probe stemming from an independence declaration, but set Carme Forcadell's bail at 150,000 euros ($175,000) and ordered her passport to be confiscated as the investigation continues.

Forcadell is speaker of the regional parliament where separatist lawmakers passed a declaration to proclaim a new Catalan republic on Oct. 27, disregarding constitutional Court warnings that such a move was illegal.

The vote was boycotted by most opposition lawmakers.

The Spanish government immediately seized control of the wealthy northeastern region, the first time in the four decades since Gen. Francisco Franco's dictatorship ended that Madrid removed powers from any of the country's 17 regions.

Central authorities also dismissed the Catalonia's regional president and his government, who are now also jailed on preliminary rebellion charges or fighting extradition to Spain from Belgium. Spain also dissolved the parliament and called a new regional election for Dec. 21.

Prosecutors are pursuing charges of rebellion, sedition and embezzlement that are punishable by up to 30 years of imprisonment under Spanish law.

Spain Supreme Court magistrate Pablo Llarena questioned Forcadell and five other members of the Catalan parliament's governing body on Thursday for more than 10 hours before deciding whether to jail them.

The judge set a 25,000-euro ($29,000) bail to be paid in one week for four of the lawmakers, and released from custody another who had made the Oct. 27 independence vote possible by allowing a debate on secession but opposed the declaration of a separate republic.

While appearing in court for questioning, Forcadell sought to avoid detention by describing the independence declaration as "symbolic," according to lawyers familiar with her testimony.

The lawyers asked not to be named because they weren't authorized to speak publicly about the court proceedings.

Catalonia's deposed regional president, Carles Puigdemont, and four of his former Cabinet members fled to Brussels, where they are fighting Spanish arrest and extradition orders.

In a letter posted on social media Thursday, the five called on voters to support pro-secession parties in Catalonia's upcoming regional election

"It's time to drive away from the (Catalan) institutions those who want to own them with a coup d'etat," Puigdemont tweeted, referring to Spain's decision to assume control of the region.

Puigdemont, who is likely to run as the regional presidential candidate for his centre-right PDeCAT party, says he went to Belgium to rally European support for the Catalan cause and that he's not trying to evade justice.

Although no country has publicly sided so far with the Catalan officials removed from office, their presence in the Belgian capital has sown divisions with fellow politicians. In Thursday's letter, the ousted Catalan Cabinet criticized the European Union for turning a blind eye to Catalonia's plight.

"The time that we spend behind Spanish bars or in exile won't be in vain if we remain united in the defence of Catalonia and in denouncing the democratic decadence of Spain," the letter said.

Spanish Prime Minister Mariano Rajoy said Thursday that his government's policy on Catalonia has "100 per cent backing" from other EU countries.

Rajoy said during a visit to the city of Salamanca, about 220 kilometres (135 miles) northwest of Madrid, that he hoped voters "meet their obligations as Spaniards and Europeans" in next month's regional election. Rajoy, who thinks a majority of Catalans don't want to break away from Spain, urged a large turnout.

European Commission President Jean-Claude Juncker, who has given Rajoy his public support, said nationalist urges are "a poison" that harm the European Union's efforts to speak with one voice on the world stage.

In what appeared to be an indirect rebuke of the secession push promoted by some Catalan leaders, Juncker said during a trip to the Spanish city of Salamanca that nobody has the right to undo the EU's model of coexistence.

Eight members of the now-dismissed Catalan Cabinet and two activists have already been jailed as the country's National Court studies whether to charge them with various crimes for allegedly creating and executing a plan to break away from Spain.

One ex-Cabinet member was released on bail, but remains a suspect in the investigation.

Forcadell remains the parliament's president, heading a commission of two dozen lawmakers during the transitional period to the Dec. 21 election.

The Supreme Court judge had delayed her questioning for more than a week after attorneys argued they weren't given enough time to prepare a defence.

Around 100 supporters chanted "You are not alone" as the lawmakers entered the Supreme Court building in central Madrid on Thursday, while police kept at bay a handful of anti-independence protesters carrying Spanish flags and shouting, "You don't fool us, Catalonia is Spain."

Fina Surina, 48, travelled overnight for nine hours from the Catalan town of Besalu to accompany the lawmakers.

They "are making a great personal sacrifice in the long-run struggle for independence," she said.

Catalonia, with 7.5 million people, represents a fifth of Spain's gross domestic product. Polls show that Catalans are roughly evenly divided over whether to seek independence or remain part of Spain.

The regional separatist authorities claimed a banned Oct. 1 secession referendum gave them a mandate to declare independence.