(CNN) A Spanish judge has ruled the former Vice President of Catalonia and three other senior Catalan pro-independence leaders will remain in jail for their part in October's independence referendum, ruled illegal by Spain's top court.

The decision limits their ability to campaign in fresh regional elections are due to be held in Catalonia on December 21.

People at a concert in support of jailed leaders hold banners reading "Freedom for the Political Prisoners."

Former Vice President Oriol Junqueras, former Interior Minister Joaquim Forn, and the leaders of the Catalonia National Assembly (ANC) and Omnium Cultural, Jordi Sànchez and Jordi Cuixar, face charges of sedition, rebellion and misuse of public funds.

"The judge does not believe there is a risk of flight, but understands the risk of a repeated offense in the case of the four people held in prison," the court statement read.

Former Vice President of Catalonia Oriol Junqueras

Six former cabinet members of the now disbanded Catalan parliament were released on bail of 100,000 euros (about $118,000.)

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