Spanish authorities have raided the Barcelona headquarters of the Convergence party and detained its treasurer as a part of a graft probe. The leader of the pro-independence party said that a "witch hunt" was underway.
A police spokesman said that at least 11 people, including the treasurer Andreu Viloca, were arrested in a series of raids on Wednesday.
The head of the region's public works department and several directors were among those arrested over a long-running investigation related to the Convergence party, the main political force behind the secessionist movement in Catalonia.
Spanish authorities suspect that the party charged commission from companies in exchange for public work projects.
Convergence party leader Artur Mas claims that he and his party colleagues are "targets of a witch hunt" over their push to break away from Spain.
"They won't find anything because there is nothing illegal in those projects," he added.
Party under suspicion
Last year, police detained a former Convergence mayor in the town of El Vendrell for allegedly receiving bribes to provide public works contracts.
Convergence founder and long-running Catalan leader Jordi Pujol resigned from all of his honorary positions last year after admitting he had kept secret foreign bank accounts with undeclared money for decades.
Several of his children are under investigation for allegedly taking money to influence distribution of public contracts.
The police also targeted the Barcelona offices of the party in August, just before the official beginning of the regional election campaign.
Walking the line
The latest arrests come as the regional leader Mas signed a decree to form a new regional parliament, following last month's vote.
Mas' coalition secured 62 seats during the September 27 polls, six seats short of an absolute majority.
Catalans largely support the right to hold a referendum on parting ways from Madrid, but are evenly divided on the issue of secession itself, surveys show.
dj/rc (AFP, AP, dpa)