Axed Catalan separatist leader Carles Puigdemont faces an extradition hearing in Belgium on Monday as Spain seeks to have him sent back to face sedition charges over his region's independence drive.
Spain wants to judge the five Catalan former leaders among others for "rebellion" (a crime punishable by 25 to 30 years in prison) and "sedition", for having successfully started a secessionist process.
Joining them was former Catalan regional president Artur Mas, a key figure in Catalonia's independence movement since 2012.
"We also highlighted the danger for the impediment of their human rights in Spain", he said.
Mr Puigdemont plans to lead his party's campaign for the December 21 regional election called by Spain's government in an attempt to find a democratic solution to the nation's worst institutional crisis in almost four decades.
The early election is an attempt to find a democratic way out of the nation's worst crisis in almost four decades.
Malta arrests 10 over slain journalist Daphne Caruana Galizia
Under Maltese law, they can be interrogated for 48 hours before a decision on whether to prosecute them has to be made. Caruana Galizia accused senior figures in both government and opposition of corruption and money laundering.
The central government's Sociological Research Centre (CIS) predicted that the three pro-independence parties would get 44.4 percent of the votes and 66 to 67 parliamentary seats out of 135, just under the absolute majority of 68.
Monday's hearing was the second time the case was discussed in court.
Campaigning for the election, with Junqueras at the head of the list for his ERC party, begins on Tuesday. The Belgian judiciary's procedure should last two months.
In a court statement, the judge ruled that, while he considered there was no risk the defendants would leave the country, he did believe there was a risk of criminal reiteration.
The magistrate also upheld custody orders without bail for the former regional interior minister, Joaquim Forn, and the leaders of Assemblea Nacional Catalan and Omnium Cultural, the two Catalan grassroots groups that have been the main drivers of the separatist bid in Catalonia.