Barcelona (AFP) - Spanish police arrested 11 people in raids in Catalonia on Wednesday as part of a graft probe targeting the wealthy northeastern region's ruling separatist party.
Among those arrested was the treasurer of the governing Convergence party, Andreu Viloca, the head of the region's public works department and seven business directors, a police spokesman said.
Police raided over 20 homes and offices as part of the operation including the Barcelona headquarters of Convergence, which has spearheaded Catalonia's drive to break away from Spain.
Spanish authorities suspect the party charged commissions from firms that won public works contracts from town halls controlled by Convergence.
The arrest came as the head of the Catalan regional government, Convergence party leader Artur Mas, signed a decree calling for the formation of a new regional parliament on October 26 following elections last month.
Mas said both he and his Convergence party were the "targets of a witch hunt" because of their efforts to secure Catalonia's independence.
"They won't find anything because there is nothing illegal in those projects," he added.
His Together for Yes coalition -- made up of Convergence and leftist separatists CRE -- clinched 62 seats during the September 27 polls, six seats shy of a majority in the 135-seat Catalan parliament.
The arrests come as Mas is seeking to get the support of the leftist Popular Unity Candidacy (CUP), whose 10 seats would give pro-secession parties an outright majority in the assembly.
During the campaign Mas vowed to set Catalonia on a path toward independence within 18 months if he gets backing from the regional parliament.
While the CUP backs secession, it has criticised Mas' support for belt-tightening measures and corruption scandals affecting his party.
Catalonia is home to 7.6 million people and accounts for one fifth of Spain's economic output.
The arrests are part of a corruption probe that began last year with the detention of former Convergence mayor of the Catalan town of El Vendrell who is suspected of receiving bribes in exchange for public works contracts.
At the end of August, police raided the Barcelona headquarters of the Convergence party and its CatDem Foundation, as well as the headquarters of former party treasurer Daniel Osacar, just as the regional election campaign was about to officially kick off.
Spanish authorities suspect the foundation collected commissions paid by companies in exchange for public works contracts.
The party was already under investigation for alleged illegal financing as part of another corruption scandal that erupted in 2009.
The founder of Convergence, Jordi Pujol, who ruled Catalonia from 1980 to 2003, resigned all his honorary positions last year after admitting he kept an undeclared fortune in tax havens for over three decades.
Six of his seven children are also under investigation for allegedly accepting bribes to help companies secure public contracts while their father was in power.