What happened in Barcelona?
A white Fiat van, reportedly rented, crashed into pedestrians outside a kosher restaurant on a busy street in Barcelona shortly after 5pm on Thursday.
The vehicle mounted the pavement and sped down the busy walkway at Las Ramblas - a busy tourist area packed with bars and restaurants - for about 500 metres mowing down pedestrians.
13 people were killed and a further 100 injured.
Victims were left sprawled in the street while others fled through the streets in panic.
Spain's civil protection agency said the injured include 26 French, four Australians, three Dutch, three Greeks and one Chinese.
What happened in Cambrils?
Residents at the Spanish seaside resort fled in terror in the early hours of Friday morning after five terrorists wearing suicide vests launched a second terror attack in a matter of hours.
Six bystanders and a police officer are reported to have been injured when the attackers drove into pedestrians in an Audi A3 on a promenade.
Police shot dead five terror suspects at the scene, just 74 miles south of Barcelona.
Police said the suspects in Cambrils carried bomb belts, which were later detonated in a controlled explosion by a police bomb squad.
The driver of the van that mowed into the packed street is still on the run this morning.
Josep Lluis Trapero of the regional police of Catalonia said two other people suspected of being involved in the terror attack had been arrested - a Spaniard and a Moroccan.
One of the suspects arrested over the attack is a man born in the Spanish territory of Melilla in northern Morocco, he said.
The other, Driss Oukabir, is Moroccan. He added that neither of them had any criminal record.
Spanish reports initially said that Driss Oukabir was being questioned on suspicion of involvement in the attack.
But on Thursday night the mayor of Ripoll, the town where he lived, 70 miles north of Barcelona, said that a man identifying himself as Driss Oukabir went to his local police station and reported that his documentation had been stolen.
Jordi Munell, the mayor, said that the man had insisted that he had been in Ripoll at the time of the attack and went to the local police station as soon as he saw his images broadcast in the media.
In a further twist, Trapero said police suspected a deadly explosion late on Wednesday at a house in Alcanar 124 miles south of Barcelona was linked to the van attack.
Trapero said the explosion left at least one person dead, and police suspected those in the house were "preparing an explosive device."
So-called Islamic State claimed responsibility
So-called Islamic State carried out the deadly van attack, the jihadist organisation's propaganda outlet Amaq said.
Amaq said they had launched the attack in response to calls to target states taking part in the United States-led coalition battling the jihadist group in Iraq and Syria.
Spanish Prime Minister Mariano Rajoy said the attack was "jihadist terrorism" which required a global response.
He said: "Today the fight against terrorism is the principal priority for free and open societies like ours. It is a global threat and the response has to be global."
IS, which once controlled a self-declared 'caliphate' across large parts of Iraq and Syria, has suffered major losses in recent months.
Coalition-backed Iraqi forces recaptured its Iraqi stronghold Mosul in July.
World leaders reaction
Prime Minister Theresa May said she is "sickened by the senseless loss of life in Barcelona.."
She added: "My thoughts are with the victims of today's terrible attack in Barcelona and the emergency services responding to this ongoing incident.
"The UK stands with Spain against terror. "Following the attacks in Manchester and London, Spain stood alongside the British people. Tonight, Britain stands with Spain against the evil of terrorism."
German Chancellor Angela Merkel said the nation is thinking of the victims of the "revolting attack" with "profound sadness."
President Donald Trump wrote on Twitter: "The United States condemns the terror attack in Barcelona, Spain, and will do whatever is necessary to help. Be tough and strong, we love you!" Russian President Vladimir Putin called for the world to unite in an "uncompromising battle against the forces of terror."
A three-year-old child is among the 13 people confirmed dead in the van rampage in Barcelona.
There was also around 100 people injured and the victims were of at least 24 different nationalities.
Those dead or injured were reported to be from countries including France, Germany, Spain, the Netherlands, Argentina, Venezuela, Belgium, Australia, Hungary, Peru, Romania, Ireland, Greece, Cuba, Macedonia, China, Italy and Algeria.
Six pedestrians and a police officer were injured in the second attack at Cambrils.
There is so far no word on whether anyone from Britain was injured or killed.