Clashes broke out between police and protesters at Barcelona's international airport on Monday.

Thousands of Catalan separatists hit the streets in protest and blocked access to Barcelona airport on Monday after Spain's Supreme Court sentenced nine of their leaders to heavy jail terms over the failed 2017 independence bid.

Advertising Read more

The long-awaited ruling capped weeks of rising tension, and puts the Catalan question at the heart of the political debate less than a month before Spain heads into its fourth general election in as many years.

As soon as news of the sentences were announced in the morning, demonstrators flooded onto the streets of Barcelona before marching towards El Prat, Spain's second busiest airport, where they choked off road and rail access.

At the entrance to the airport, police in riot gear repeatedly charged at protesters trying to get inside. Demonstrators responded by throwing rocks, cans and fire extinguishers.

At one point, traffic outside came to a complete standstill up to five kilometres (three miles) from the airport, with many travellers with suitcases getting out of cars and walking as a police helicopter flew overhead.

Spanish airport authority AENA airport authority said 108 flights had been cancelled.

Police arrested one protester at the airport while 53 people were injured.

Spanish press reacts to sentencing of Catalan separatist leaders over failed independence bid 02:08

In the evening thousands of people gathered in Barcelona, chanting "The streets will always be ours" and other slogans. Many carried Catalan separatist flags.

"If they don't want to listen to us by engaging in politics, then they must hear us in the streets," said Mireia Sintes, a 26-year-old architecture student at the Barcelona rally.

Scuffles broke out between police and protesters at the end of the rally after some people refused to leave a major thoroughfare.

'Revenge'

Since the early hours, police have been braced for what activists pledged would be a mass response of civil disobedience. Roads have been closed in various parts of the region while rail traffic has also been hit.

"I feel very affected by the sentence even though I expected it. I feel fury and a sense of powerlessness," said Joan Guich, a 19-year-old maths student who was protesting on Barcelona#'s main thoroughfare, Gran Via, in the afternoon.

"They have been convicted for an ideology which I agree with."

Catalan leaders trial: "A dark day for fundamental rights" 05:16

The 12 defendants were put on trial in February for their role in the banned October 1, 2017 referendum and the short-lived Catalan independence declaration that followed it.

The harshest sentence of 13 years was handed to former Catalan vice president Oriol Junqueras who served as the main defendant in absence of Carles Puigdemont, the region's leader who fled Spain to avoid prosecution.

"This is not justice, it is revenge," the nine defendants who were sentenced to jail said in a joint letter.

'Turn the page'

And in a separate letter released on Monday, Junqueras said the story was far from over. "We will come back even stronger... and win."

In a tweet from Brussels, Puigdemont denounced the sentences as an "outrage".

"100 years in all. An outrage. Now more than ever, by your side and those of your families. It is time to react as never before," he wrote.

Spain's government has expressed hope the trial's end would allow it to move on from the crisis in the wealthy northeastern region, where support for independence has gained momentum over the past decade.

"Following the Supreme Court decision, we need to turn the page... through dialogue," Prime Minister Pedro Sanchez said, speaking in English.

But shortly afterwards, a judge issued a new international arrest warrant for Puigdemont, a clear indication Spain would not rest until he and five others who fled abroad had been tried for their role in the crisis.

'Outraged'

The separatist movement is hoping the guilty verdicts will unite their divided ranks and bring supporters onto the streets.

"It is time to rise up against the authoritarian fascism of the Spanish state and its accomplices," tweeted the radical CDR, as thousands heeded the call to protest.

Many said they had taken the day off to protest sentences they knew would be harsh.

'The Catalan independence movement was always peaceful,' Jordi Savall tells FRANCE 24 00:42

"I'm not surprised but I still feel really outraged. These are good, peaceful, honest people," said Carles Navarro, a 49-year-old IT consultant.

"We have always looked for a peaceful way (to express our demands) but nobody listens. Now we're forced to resort to civil disobedience."

In the coming days, demonstrators plan to march from five towns towards Barcelona where they will congregate on Friday, when a general strike has been called.

(AFP)

Daily newsletterReceive essential international news every morning Subscribe