BARCELONA, Spain — Thousands of pro-Catalan independence supporters on Tuesday protested the start of a Spanish court investigation into the regional government's symbolic referendum on secession from Spain last year.
New Barcelona mayor Ada Colau headed the demonstration, reading a statement backing Catalonia's demand for the right to self-determination. The rally came after a regional official and a former regional deputy president were questioned over their suspected roles in holding the poll.
Catalonia's regional leader Artur Mas is also under investigation and is scheduled to testify Thursday.
Spain's Constitutional Court suspended the Nov. 9, 2014, referendum but Catalonia held it anyway, calling it an informal effort.
Prosecutors accuse Mas of grave disobedience, abuse of public funds, prevarication, usurping powers and obstructing justice. If tried and found guilty, he could face disqualification from office or up to one year in jail.
About 2.3 million Catalans — out of 5.4 million eligible — voted in the poll, with 80 percent in favor of breaking away from Spain. Spain's Constitutional Court later ruled the plebiscite was unconstitutional.
Catalonia last month held a regional parliamentary election that was billed as a de facto vote on secession. The "Together for Yes" pro-independence alliance headed by Mas won 62 seats in Catalonia's 135-member parliament — six short of a majority.
That alliance is currently in negotiations with another pro-independence party to try to form a coalition majority, and Mas has promised to set Catalonia on a path toward independence by 2017 if he gets the majority.
Spain has ruled out any possibility of Catalonia becoming independent, saying that would be unconstitutional.
Giles reported from Madrid. Alan Clendenning contributed from Madrid.