Image source, EPA

A memorial for victims of the Spanish attacks has been set up in Berlin, which suffered a similar tragedy last December when a truck was driven into a Christmas market, killing 12 people.

What looked at first to be a lone-wolf attack by just one, or possibly two, individuals has now emerged as a complex plot involving at least eight suspects, armed with knives and explosives, writes BBC security correspondent Frank Gardner

It suggests both an element of careful planning by the perpetrators and also a failure of intelligence by the normally vigilant Spanish authorities, he adds.

BBC Monitoring
The world through its media

Germany's newspapers have reacted with shock to the attacks in Spain.

Der Tagesspiegel , externalfront page says "Terror in the heart of Barcelona", while Suedeutsche Zeitung , externalruns the headline "Stab in the heart of the tourist metropolis".

Suedeutsche Zeitung says: "It was a targeted attack in the heart of Spanish tourism, the country’s main industry... They wanted not only to kill people, but also to sow fear among those who are planning to holiday in Spain."

Frankfurter Allgemeine Zeitung , externalnotes "the incident is likely to put security issues in focus in the Bundestag election campaign".

Image source, BBC Monitoring

The emergency services in Catalonia say autopsies took place overnight:

Image source, TOMSHW.IT

Bruno Gulotta, a 35-year-old father-of-two, was one of two Italian nationals killed in the attack on Las Ramblas.

Paying tribute to the kindness and generosity of their co-worker, Gulotta's colleagues said his violent death had left his wife facing "trials no-one should have to bear".

Italy's La Repubblica newspaper reported that he had been walking with his wife, who managed to pull their five-year-old son from Bruno's hand to safety at the last moment.

The second victim was named by Italian PM Paolo Gentiloni as 25-year-old Luca Russo. He was in Barcelona with his girlfriend, who was also injured in the attack.

"Italy will remember Bruno Gulotta and Luca Russo and expresses its solidarity with their families," Prime Minister Paolo Gentiloni said in a tweet, external.

"Freedom will triumph over barbarism and terrorism."

Read more about the victims

People in Spain share uplifting images of cats after being asked not to post pictures of the Barcelona victims.

Reuters

One of the people killed in the Spanish attacks was an American, Reuters reports, citing the US Secretary of State Rex Tillerson.

One police officer killed four of the attackers in Cambrils, Catalan police chief Josep Lluis Trapero has told journalists.

Around eight hours after the van attack killed 13 people in Barcelona, an Audi A3 car ploughed into pedestrians in the seaside resort of Cambrils.

The vehicle overturned and when the attackers got out, they were shot at by police. Four died at the scene and one later died of his injuries

Some of the attackers were wearing explosive belts, which police have since confirmed were fake.

Image source, Anna Lindsay

At the scene

Anna Lindsay, BBC News

Spontaneous singing of the John Lennon song "Imagine" broke out among those gathered to pay respects and lay tributes on Las Ramblas.

A crowd had formed a circle around the place where the van used in Thursday's attack came to a stop.

Commemorative candles and flowers are beginning to fill the area.

But a sign of just how nervous everyone is here: During the song police whistles were blown, an engine roared and many people ran for cover.

It turned out to be an emergency vehicle, but feelings are running very high despite Las Ramblas being filled once more with tourists and residents alike.

The Cambrils attackers managed to wound one person in the face with a knife before they were shot, Catalonia police have said.

As well as numerous knives, an axe was also found at the scene, police said through their official Twitter account.

They also confirmed the "suicide vests" the attackers used were fake.

US President Donald Trump has taken to Twitter to call for the courts to give back America's "protective rights" in the wake of the Spanish attacks.

Mr Trump has been arguing for tougher controls to prevent people entering the United States since before he took office.

Others have suggested the President has an anti-Muslim agenda.

BBC Monitoring
The world through its media

Supporters of so-called Islamic State are hoping the attack in Barcelona will put pressure on the Spanish government to pull out of the international anti-IS coalition.

Jihadists have often praised the Madrid train bombings of 2004 that killed 192 people as a model of jihadist action that had instant results.

The 2004 attack, which was loosely linked to al-Qaeda, directly affected the results of the Spanish national elections held three days later and influenced Spain pulling its troops out of Iraq.

Jihadists considered this incident a major victory and have since longed for a similar impact.

Through attacks in its name, IS is hoping to create fear and panic among the Western electorate in the hope that they will put pressure on their governments to leave it alone.

A pro-IS channel on the messaging app Telegram has issued a flurry of posts in Arabic and Spanish. They addressed the Spanish people telling them that their government was to blame for the attack.

One post in Spanish read: "O people of Spain, do not take to the streets to protest against terrorism, for you won't gain anything. Put pressure on your government to withdraw from the Crusader coalition."

Others warned Spaniards of more attacks to come if they did not take action against their government. "O people of Spain, what happened today in #Barcelona will not end. It's just the beginning", read one post.

A prominent IS channel on Telegram called "Muhalil Askari" (military analyst) praised "the unique blow in the heart of usurped Andalusia", making reference to a part of Spain that was under Muslim caliphate rule between the years 711 and 1492.

The analysis the channel offered pointed to potential political impact.

It said: "The Barcelona attack took place in Catalonia, the region seeking to separate from Spain.

"This region is now paying the price for the politics of mainland Spain that have put it [Catalonia] in an alliance against a fierce enemy [IS] that has no mercy on its enemies."

Catalonia has announced plans to hold a referendum on independence from Spain on 1 October. Voters will be asked “do you want Catalonia to be an independent country in the form of a republic?”

Image source, EPA

The Barcelona and Cambrils attackers had been planning bigger attacks than the ones they carried out, police have said.

Catalan police chief Josep Lluis Trapero told a press conference officers believed the group had been preparing the attacks at a home in Alcanar.

But an explosion in the house on Wednesday, which killed one person, wounded seven and destroyed material they were planning to use in the attacks, meant they had to carry them out in a "more rudimentary way", Mr Trapero said.

The four people arrested include three Moroccans and one Spanish national, police have said.

None of them had a criminal history relating to terrorism, police chief Josep Lluis Trapero told a press conference.

Three were arrested in the village of Ripoll and one in the town of Alcanar, where the house at the centre of the investigation exploded on Wednesday night.

The youngest person arrested was 21, while the others were 28, 34 and 27 years old, Mr Trapero said.

Theresa May says countries must work together to confront terrorism.

Image source, EPA

Barcelona has “sent a very clear message to the terrorists”, according to the Catalonian Regional President Carles Puigdemont.

Speaking at a press conference, Mr Puigdemont, said: “We woke up concerned, but also determined to win – to win this battle against terrorism, doing it in the best ways our society has: solidarity, freedom and respect.”

The Spanish prime minister, Mariano Rajoy, said terrorism was a "global battle".

"It is not only against us, it is against all those that defend democracy, freedom and human rights," he said.

On Saturday, Mr Rajoy said he will go to Madrid to decide whether the country's terror threat level - which is currently at level 4 - should be increased as a result of the attacks.

Theresa May has said UK authorities are "urgently" looking into reports of a missing British child.

The Prime Minister said she believed a number of British people have been caught up in the attack.

She said the missing boy had dual-nationality, but did not name him.

Earlier, appeals were launced to find a seven-year-old Australian boy who has not been seen since the attack on Las Ramblas on Thursday.

Julian Cadman had been in Barcelona with his mother, who is currently in hospital.

Images from the scene after a van rammed crowds in Barcelona's popular tourist hotspot, Las Ramblas.