Oct. 15 (UPI) -- Police in Spain are preparing to square off with protesters again Tuesday after the country's Supreme Court sentenced nine Catalonia separatists to up to 13 years in prison on sedition charges.
Catalonia independence demonstrators blocked passenger trains, bogged down busy roadways and caused more than 100 flights to be canceled Monday. Protesters gathering at Barcelona's main airport Tuesday threatened international American Airlines flights to New York, Miami, Chicago and Philadelphia.
Monday's ruling and protests are outgrowths of a Catalonia independence referendum two years ago that the Spanish government declared was illegal. Citizens in the region overwhelmingly voted for independence.
Although the nine separatists were found guilty of sedition, they escaped the more serious charge of rebellion. Three other separatists found guilty of disobedience did not receive any prison time.
Widespread demonstrations fanned out around the region after the verdict. Organized protests at Barcelona's Josep Tarradellas-El Prat Airport forced airlines to cancel flights. Motorists, buses and taxis waited in lines for hours because of street protests.
Local police said that about 25,000 protesters gathered at Catalunya square before the demonstration at the airport, which prevented crews from reaching their planes for takeoff.
Spain's Acting Interior Minister Fernando Grande-Marlaska said on Tuesday the government will investigate Tsunami Democratic, the grassroots group that helped organize the protests at the airport.
"Of course there are investigations, we have efficient intelligence services and we will end up knowing who is behind these actions by Tsunami Democratic," Grande-Marlaska said.