One of the terrorists who ploughed a car into pedestrians in the Spanish seaside town of Cambrils on 18 August sent a friend a message via WhatsApp hours before the attack, promising to meet up later that week "if he has time."

Houssaine Abouyaaqoub and four other terrorists were shot dead by Catalan police after they drove a black Audi through a crowd of people in Cambrils, killing one and injuring several others.

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After crashing the car, they emerged from the vehicle carrying machetes and axes. One police officer was hailed as a hero after he gunned down four of the terrorists single-handedly.

Hours before carrying out his deadly attack, Abouyaaqoub exchanged messages with a friend who asked where he had "disappeared" in recent weeks, Catalan newspaper Ara reported.

"Hey man, you've been missing," his message to Abouyaaqoud read. The terrorist responded: "Yeah, I have some work this summer. I want to buy a car."

When his friend asks him if he wants to do go-karting in Roses, a town in Catalonia, that week, Abouyaaqoub replies: "Ok, perfect. If I have time I'll tell you something ok?"

The messages were sent shortly after Abouyaaqoub's brother, 22-year-old Moroccan national Yunes, carried out a vehicle attack in the centre of Barcelona, killing at least 13 people and injuring dozens more, and hours before the attack in Cambrils.

Yunes was shot dead on Monday (21 August) by Catalan police after they confronted him in Subirats, an area 25 miles (40km) west of Barcelona, hours after authorities named him as the prime suspect in their investigation and extended a manhunt for the driver across Europe.

The brothers were both members of a 12-strong terror cell, based in Ripoll, a town in northern Catalonia, where an imam linked to the deadly 2004 Madrid train bombings is thought to have radicalised the men.

After the attacks, police discovered the cell's bomb-making unit at a house in Alcanar, a town south of Barcelona, where they found 120 gas canisters and the remains of the Ripoll imam, Abdelbaki Es Satty.