The mayor of riot-stricken Barcelona has called for calm after violent protests by Catalan separatists rocked Spain’s second largest city once again.

Mayor Ada Colau said that “this cannot continue. Barcelona does not deserve it”.

Ms Colau said Friday’s violence was worse than that of the four preceding nights.

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A woman crosses through a street full of rubble during clashes between police and Catalan pro-independence protesters (AP)

Protesters have been angered by Monday’s Spanish supreme court verdict that sentenced nine separatist leaders to prison.

Radical separatists have clashed with police each night in Barcelona and other Catalan cities following large peaceful protests.

Outnumbered police used tear gas and water cannon on Friday night to battle rioters in Barcelona, a major tourist destination.

“The images of organised violence during the night in Barcelona have overshadowed the half a million people who demonstrated in a peaceful and civic manner to show they rejected the verdict,” said Catalan interior chief Miquel Buch, who oversees the regional police.

Rioters have burned hundreds of rubbish bins and hurled petrol bombs, chunks of pavement and firecrackers, among other objects, at police. They have used nails to puncture the tyres of police vans.

Residents and tourists have run for cover.

Catalan pro-independence clash with police in Barcelona
Catalan pro-independence clash with police in Barcelona (Bernat Armangue/AP)

“It has been quite scary,” Deepa Khumar, a doctor from Toronto visiting for a medical conference, said on Friday.

“This place, it looks like a war zone.”

Authorities said over 500 people have been hurt this week, including protesters and police, while police have made over 150 arrests.

Spanish interior minister Fernando Grande-Marlaska said on Saturday that 101 police officers were injured on Friday alone and that 264 police vehicles have been severely damaged in the week’s riots.

Mr Grande-Marlaska asked Catalonia’s regional president to explicitly condemn the escalating violence and express his support for law enforcement officials.

Police officers run past a burning barricade on the fifth day of protests
Police officers run past a burning barricade on the fifth day of protests (Manu Fernandez/AP)

“We have gone five days in which there has not been a firm condemnation of violence” by Catalan leader Quim Torra, Mr Grande-Marlaska said.

Mr Torra has called on protesters to respect the non-violent principles of the separatist movement that has surged over the past decade.

But on Saturday, Mr Torra and his vice president, Pere Aragones, used a televised address mostly to criticise the Supreme Court verdict.

Mr Torra demanded to meet Spain’s prime minister Pedro Sanchez to push his agenda for secession and freedom for the prisoners.

The prime minister’s office responded that “the government of Spain has always been in favour of dialogue, but within the confines of the law”.