There have been two attacks in Spain’s Catalonia region involving people driving cars at crowds at high speeds. Here is what we know so far.

What happened?
On Thursday afternoon at 16:50 local time (14:50 GMT) a white van smashed into people on Las Ramblas, a famous boulevard in central Barcelona that runs 1.2km (0.75 miles) and was packed with tourists.

The van driver is said to have zig-zagged to try and hit as many people as possible along the pedestrianised area, knocking many to the floor and sending others fleeing for cover in shops and cafes.

He killed 13 people and injured more than 100, and managed to flee the scene. Spanish police have described it as a terror attack.

What was the second attack?
About eight hours later, an Audi A3 car ploughed into pedestrians in the popular seaside resort town of Cambrils, 110km (68 miles) south-west of Barcelona, authorities said.

A woman who was critically injured later died in hospital. Five other civilians and a police officer were hurt.

The attackers’ vehicle overturned and five people who got out, some of whom were wearing fake suicide belts, were then shot by police. Four died at the scene and one later died of his injuries.

Spanish police stop second attack
The Las Ramblas and Cambrils attacks are believed to be linked.

Who are police looking for?
A massive manhunt is under way to find 18-year-old Moussa Oukabir. He is suspected of using documents belonging to his brother, Driss Oukabir, 28, to rent the van that mowed down people on Las Ramblas.

Police say they cannot yet confirm he was the driver of the van, who fled on foot. Driss Oukabir was arrested in Ripoll, a town in Catalonia, on Thursday.

Who else has been arrested?
Three others. One person from Spain’s north African enclave of Melilla was arrested in Alcanar on Thursday, and two others were arrested on Friday, one in Ripoll.

Police said on Friday that three of those arrested were from Morocco and one was from Spain, but gave no details. It remains unclear how many people were involved in the plots.

What were the other incidents?
On Thursday evening at 19:30 local time, a car was driven into officers at a checkpoint on the outskirts of Barcelona.

The car was later found with a dead man inside it, but the interior ministry has denied earlier reports he was killed by police gunfire. Officials have not ruled out a connection with the Las Ramblas attack but investigations are ongoing

On Wednesday night, an explosion completely destroyed a house in Alcanar, 200km south of Barcelona, killing one person and wounding seven. The house was reportedly filled with bottles of propane and butane.

Who are the victims?
They come from all over the world, with at least 34 nationalities represented.

People from Ireland, the UK, France, Australia, Pakistan, Venezuela, Algeria, Peru, Germany, the Netherlands, Greece, Hong Kong, Taiwan, Ecuador, the US, Argentina, Romania, Cuba, Austria and the Philippines are all reported to be among those hurt.

Francisco López Rodríguez, a 60-year-old from Granada, is the first Spanish victim to be named. Belgium said one of its citizens had been killed and Italy’s foreign ministry said two Italians had died.

France said 26 of its nationals were injured, 11 seriously. The Australian government said at least four citizens were injured, while a seven-year-old boy from Sydney is reported to be missing. Thirteen German citizens were wounded, some seriously.

Who is responsible?
So-called Islamic State (IS) has said it was behind the Las Ramblas attack and that IS “soldiers” carried it out. But it did not provide any evidence or details to back up the claim.

Why Spain?
The country is one of Europe’s most popular tourist destinations but in recent years has not seen the kind of jihadist violence that has rocked France, the UK, Belgium and Germany.

Still, Spain has been targeted before – several trains in Madrid, the capital, were bombed by al-Qaeda inspired militants in 2004, killing 191 people.