At least 13 people have died and around 80 have been injured after a van ploughed into pedestrians in a terror attack in a busy tourist area of Barcelona.
Spanish police arrested two people after a white Fiat van tore through the Las Ramblas district which was packed with shoppers and holidaymakers.
The vehicle careered into terrified pedestrians in the busy tree-lined promenade, one of the most popular parts of the city.
Local media said police were hunting a man named Driss Oukabir who is suspected of having rented the van used in the attack. The passport of a Spanish citizen, of Moroccan origin, was found at the scene.
The identity of those arrested is not clear.
There were also reports that detectives believe two vans were used, one for the attack and a second as a getaway vehicle.
Unconfirmed local reports suggested an attacker had been shot by police on the outskirts of the city.
Police also said a driver had run over two police officers in a town north of the city, but it was not clear if this was related to the attack.
The Islamic State terror group has claimed responsibility.
The terror group has frequently declared that it was behind terrorist incidents in recent years, but experts have warned their claims should be treated with caution.
The terror attack - the deadliest on Spanish soil since more than 190 people died in the Madrid train bombs in 2004 - brought widespread condemnation.
Carles Puigdemont, the president of Catalonia, confirmed the two arrests at a press conference.
He also said 12 people were confirmed dead and at least 80 taken to hospital, which conflicted with interior minister Joaquim Forn, who said 13 people had died.
A Belgian national is among the dead, Belgium's deputy prime minister Didier Reynders confirmed on Twitter.
Catalonian police said 15 people were seriously injured in the attack.
The Government of Catalonia said Mr Puigdemont had declared three days of mourning for the region.