Spanish police have killed the key suspect in the bus attack which occurred in

The suspect identified as Moussa Oukabir was one of the five men killed by police in the other attack site, Cambrils.

Earlier, the police had said they were searching for Oukabir and three other men - with four other suspects now arrested, only one of them is unaccounted for.

Oukabir rented the van that rammed into a crowd, killing 13 people in Barcelona's Ramblas district.

Police said the suspects were planning more sophisticated attacks.

Authorities said blasts on Wednesday in Alcanar, a town south of Barcelona, deprived the attackers of bomb material so they carried out simpler attacks using vehicles.

Moussa Oukabir, thought to be 17, was a Spanish citizen from the northern Catalan city of Girona. Most of the other suspects were Moroccans.

He is suspected of using his brother's documents to rent the van used in the Barcelona attack and another found hours later in the town of Vic, north of Barcelona, that was intended as a getaway vehicle.