Thousands of people rally outside the regional presidential palace in Barcelona on Tuesday to show their support for those appearing in court. (Manu Fernandez/AP)

A Spanish judge on Thursday ordered the jailing of eight of Catalonia's separatist leaders a week after the region declared independence, extending the tough crackdown on the breakaway effort.

The decision not to free the former officials on bail ahead of their trials on charges of rebellion, sedition and the misuse of public funds came after an Oct. 27 takeover of the region following the Catalan Parliament's vote to secede.

The imprisonments set off an immediate outcry from independence advocates in Catalonia, who said they fit into a repressive pattern from the Spanish state that began when national police intervened with truncheons and violence to try to prevent an independence referendum from being held on Oct. 1. Town squares across Catalonia filled with protesters after the decision was announced late Thursday afternoon.

A prosecutor also asked Judge Carmen Lamela to approve an international arrest warrant for former Catalan president Carles Puigdemont, who fled to Belgium on Monday alongside other officials. An extradition request would set the ground for a difficult diplomatic dance between Spain and Belgium, which allows E.U. citizens to claim political asylum and which is partly ruled by Flemish nationalists sympathetic to the Catalan cause.

Lamela planned to decide on the warrant Friday. In denying bail, she said the leaders still in Spain were a flight risk, citing the retreat by Puigdemont and others to Brussels.

[How Catalonia’s independence went from dream to defeat in just a month]

Puigdemont refused to appear at the Madrid court on Thursday, saying that the charges were politically motivated. The leaders are facing prison terms of up to 30 years. In all, 20 officials are charged.

Apart from the eight people sent to jail Thursday, a ninth was allowed free on bail of $58,000 because he resigned from the Catalan government before the independence declaration.

"A long and fierce repression lies ahead. We must combat the situation as Catalans do, without violence, in peace," Puigdemont said Thursday in a televised address to Catalans that appeared to be recorded in his Brussels hotel room. He has said that he remains Catalonia's leader and that the decision by Spanish Prime Minister Mariano Rajoy to use constitutional powers to strip him of office was illegal.

The decision to put the former officials behind bars meant that the highest-profile Catalan separatist leaders will probably not be able to run in Dec. 21 regional elections that Rajoy called after dismissing the government. After darkness fell Thursday, the former officials were transferred in police vans with flashing blue lights to the Alcala-Meco Prison outside Madrid.

The move was condemned even by some pro-union Catalan leaders, who said it was needlessly harsh.

[Catalan separatists counted on support from the E.U. They got the cold shoulder.]

"This is a black day for democracy and for Catalonia," said Barcelona Mayor Ada Colau, who appeared close to tears as she spoke to journalists late Thursday. Colau has said she believes Catalonia should have more autonomy but should not be independent.

The crackdown drew condemnation from several other leaders in Europe, including the heads of Scotland and Belgian Flanders, two regions that have sought independence or more autonomy from their national governments.

"Jailing democratically elected government leaders = more than bridge too far," the leader of Belgium's Flanders region, Geert Bourgeois, wrote on Twitter.

That was echoed by Scottish First Minister Nicola Sturgeon, who wrote that "regardless of opinion on Catalonia, the jailing of elected leaders is wrong and should be condemned by all democrats." She added: "The disagreement about Catalonia's future is political. It should be resolved democratically — not by the jailing of political opponents."

Opinion polls show that support for independence in Catalonia is growing but that slightly less than half of the population seeks a split.

Braden Phillips contributed to this report.

Read more:

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How Catalonia’s crisis is turning into a European problem

The future of Catalonia may well hinge on an 84-word section of the 1978 Spanish Constitution

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