Spain's La Liga returns on Friday under the shadow of terrorist attacks in Barcelona and Cambrils that left 14 killed and more than a hundred injured.

The league's authorities still plan for all 10 La Liga fixtures to take place, including Barcelona's match at home to Real Betis on Sunday.

All games across the top two divisions will be preceded by a minute's silence.

"LaLiga has asked the RFEF (Spanish Football Federation) to hold a minute's silence in all matches of the first day of the competition in LaLiga Santander and LaLiga 1l2l3," La Liga said in a statement.

Barca's players held a minute's silence before training on Friday, while the club published a picture of the players and coaching staff with the hashtag "TotsSomBarcelona" ("We are all Barcelona") on its social media channels.

"As a mark of respect, the flags will fly at half-mast at the club’s facilities and the players from both teams will wear black armbands in all the club's matches this weekend," Barca added in a statement.

Barcelona's other top-flight side Espanyol are away to Sevilla on Saturday.

"With our hearts still shrinking to see Barcelona, our beloved Barcelona, attacked vilely by terror and hate, we want to show our solidarity with all the people affected as well as to thank enormously all the support received by both the city and our club," Espanyol said in a statement.

The league's biggest stars Lionel Messi and Cristiano Ronaldo were among those to lead tributes to the victims as the shocking events of Friday unfolded.

"I want to send my condolences and all my support to the families and friends of the victims of the terrible attack in our beloved Barcelona, in addition to totally rejecting any act of violence," Barca forward Messi, wrote on Instagram.

"We are not going to give up, there are many more of us who want to live in a world in peace, without hate and where respect and tolerance are the basis of coexistence."

Ronaldo and his Real Madrid teammates also showed their solidarity with Barcelona as the two clubs' fierce rivalry was forgotten at a tragic time.

"Dismayed at the news coming from Barcelona. All the support and solidarity (to) the family and friends of the victims," Ronaldo wrote on Twitter.

That mood was reflected on the front pages of Spain's sport newspapers on Friday.

"Today we can't talk about sport," splashed Madrid-based Marca.

Taking a line from Barca's club anthem, Barcelona-based Sport's headline ran "Tots units fem força" (together we are stronger).

The first league matches of the season take place on Friday night when Leganes welcome Alaves in Madrid before Valencia host Las Palmas.

Newly-promoted Girona host Atletico Madrid in the first game in Catalonia since the attacks, just over 50 miles north-east of Barcelona on Saturday.

"The most important thing is what happened yesterday," Atletico coach Diego Simeone said on Friday.

"Unfortunately it was a very hard day for everyone.

"I express my solidarity, sadness and encourage all those that want to live in peace."

Fixtures (all times GMT)

Friday

Leganes v Alaves (1815), Valencia v Las Palmas (2015)

Saturday

Celta Vigo v Real Sociedad (1615), Girona v Atletico Madrid (1815), Sevilla v Espanyol (2015)

Sunday

Athletic Bilbao v Getafe (1615), Barcelona v Real Betis (1815), Deportivo la Coruna v Real Madrid (2015)

Monday

Levante v Villarreal (1815), Malaga v Eibar (2000)