Barcelona stars past and present have expressed their shock and sadness at the terror attack in the city.
A van ploughed into pedestrians in the busy tourist area of Las Ramblas on Thursday.
Lionel Messi, Luis Suarez and Neymar were among those to condemn the attack in which at least 13 people died and more than 50 were injured.
Messi said on Instagram: "I would like to send my condolences and all my support to the families and friends of the victims of the terrible attack on our beloved Barcelona, as well as totally reject any act of violence.
"We are not going to give up, we are many more who want to live in a world in peace, without hate and where respect and tolerance are the basis of coexistence."
Former Liverpool striker Suarez said on Twitter: "Very shocked for what happened in Barcelona. All my support to the city and families!"
Club captain Andres Iniesta tweeted: "Everyone is ashamed of what has happened and the news that continue to come out of our city. All my love."
Defender Gerard Pique said: " More than ever all together against this attack in our city. All my support to those affected by this barbarism. #Barcelona."
Neymar, who left Barcelona for Paris St Germain this summer in a world-record 222million euro (£200.6million) move, tweeted: " May God comfort all families #PrayForBarcelona I love you BARCELONA."
Ronaldinho won two league titles and the Champions League during a glittering five-year spell at the Nou Camp, during which he also won the Ballon d'Or.
He tweeted: "Too sad to see the news coming from #Barcelona. My support and solidarity for the victims and families."
Former England striker Gary Lineker played for Barcelona for three seasons from 1986-89.
He said on Twitter: "Deeply saddened to hear about the attack in the wonderful city of Barcelona. What purpose this barbarity serves is beyond comprehension."
Barcelona themselves said they were "deeply saddened by the attack" and the club's thoughts were "with the victims, their families and with the people of Barcelona".
Their LaLiga rivals Real Madrid expressed their "deepest dismay" and their "solidarity with the victims and their families and friends" in a statement on their official website.
Real striker Cristiano Ronaldo, who was sent off in Monday's Supercopa first leg at the Nou Camp, added on Twitter: "Dismayed at the news coming from Barcelona. All the support and solidarity with the family and friends of the victims."
Manchester City, managed by former Barcelona midfielder and manager Pep Guardiola, said: "All at MCFC are saddened to hear of the attack in the City of Barcelona. Our thoughts are with all affected and the emergency services."
Spain's 15-time grand slam champion Rafael Nadal, whose uncle Miguel Angel Nadal played for Barca from 1991-99, said: "Shattered by what has happened in Barcelona! All my support for the families affected and the city."
The Spanish Football Federation issued a statement expressing its "total condemnation" of the attack.
The statement added: "It also wants to convey its condolences to the families of the victims and to wish a speedy recovery for the injured.
"The whole family of Spanish football shows all their support to those affected and their loved ones in these hard times and expresses its absolute repulsion of any form of violence."
The Spanish league season starts this weekend, with Barca hosting Real Betis in their opening game on Sunday.
Espanyol, the city of Barcelona's other top-flight team, tweeted: "The most beautiful city in the world, our city. We suffer with you and with all the people of Barcelona. Strength and encouragement, Barcelona!"