Spain's interior minister warned in an interview published Sunday there was a "real" risk that Catalan government's push for independence could degenerate into violence.

"A process of these characteristics, by its very nature, generates radicalism. And all radicalism, in and of itself, is negative," Jorge Fernandez Diaz told conservative daily newspaper ABC.

Spain's Prime Minister Mariano Rajoy on Wednesday branded the Catalonia region's symbolic vote on independence a failure but said he was open to constitutional reform to answer Catalan demands.

"We have witnessed a deep failure for the independence movement," Rajoy told a news conference, adding that constitutional reform was "the only legal and responsible course".

Spain's government Tuesday rejected Catalonia's calls for self-determination after more than two million people took part in a symbolic vote on independence for the region.

Catalonia's leader reached out to Madrid for talks on a "definitive" and binding vote, but the national government, which had tried to ban Sunday's ballot, dug in its heels.

More than 300 African migrants tried to scramble over the border fence from Morocco into the Spanish territory of Ceuta on Tuesday, the local authorities said.

Two groups approached the wall one after the other before dawn but were prevented by the Moroccan police from climbing over, a Spanish government spokesman in the territory told Agence France Presse.

Luis Guevara hoped politicians in Catalonia would turn their focus to the economy after Sunday's symbolic independence referendum, but now he fears a strong turnout at the poll means more wrangling with the Spanish government.

"Of course it worries me," the 53-year-old owner of a struggling property management firm said as he went on a walk with his wife on the seaside promenade in Badalona, an industrial city near Barcelona, the Catalan capital.

Catalonia's nationalist government prepared Monday to step up its secession drive after more than two million people voted in a symbolic independence referendum which Spain's central government dismissed as "useless".

The head of the Catalan regional government Artur Mas called Sunday's vote, which was ordered blocked by the constitutional court at Madrid's request, "a total success" after the overwhelming majority of those who took part supported independence.

Twelve people died when a coach plunged into a ravine in the Murcia region of southeast Spain, in the worst such accident in the country for six years, officials said Sunday.

The coach carrying passengers from the village of Bullas back from the capital Madrid left the road and turned onto its side in a ravine just before midnight Saturday.

More than a million Catalans turned out Sunday to vote on independence from Spain in a symbolic ballot, defying challenges from the Spanish government.

Voters of all ages lined up around the block, some applauding, as polling stations opened after weeks of tense legal wrangling with Spanish authorities.

Catalan leader Artur Mas said Saturday that any steps taken by Spain's central government to disrupt a symbolic vote on independence in the wealthy region would be "a direct attack on democracy".

Spain's Constitutional Court this week ordered the Catalan government to suspend Sunday's vote but Catalonia's nationalist government has vowed to press ahead with the ballot, which will be organized by volunteers without an official electoral roll.

One of Spain's biggest and richest regions, Catalonia will defy Madrid on Sunday when it holds a symbolic vote on whether it should break away as an independent state.

Despite the fierce opposition from Madrid, Catalan leaders have stuck by their vote plan in a constitutional standoff unprecedented in post-Franco Spain.