World leaders have sent messages of support to Spain after a vehicle attack in Barcelona killed at least 13 civilians.

Candles and bunches of flowers placed by people rest on the ground in Las Ramblas, Barcelona, Spain, August 18, 2017.
Candles and bunches of flowers placed by people rest on the ground in Las Ramblas, Barcelona, Spain, August 18, 2017. (AP)

In an incident claimed by Daesh, a white van rammed into pedestrians on a street full of tourists in central Barcelona on Thursday afternoon, killing at least 13.

Some eight hours later in Cambrils, a town 120 kilometres south of Barcelona, an Audi A3 car rammed into pedestrians, injuring seven, one of them critically, authorities said.

There were at least 18 nationalities among the dead and injured from both attacks including France, Italy, Turkey, Venezuela, Australia, Ireland, Peru, Algeria and China, according to officials.

There's been an outpouring of support for Spain and its citizens from leaders around the world.

President Recep Tayyip Erdogan offered his condolences to Spain's King Felipe VI and expressed his sadness over the loss of lives of innocent people.    

"I strongly condemn the attack, which once again reveals the brutal face of terrorism, a threat to not only Spain but the common values of all humanity" Erdogan said in a message to King Felipe.       

The president also emphasised that Turkey is in full solidarity with Spain, saying he shares the pain of the Spanish nation.

Turkish Foreign Ministry Mevlut Cavusoglu also spoke out via social media.

US President Donald Trump pledged support for Barcelona via tweets.

In another tweet, he referred to an early 20th century American general who is said to have shot Muslims with bullets dipped in pigs' blood in the Philippines. 

Former US president Barack Obama also shared his condolences.

As well as French President Emmanuel Macron.

UK Prime Minister Theresa May said, "My thoughts are with the victims of today's terrible attack in Barcelona and the emergency services responding to this ongoing incident. The UK stands with Spain against terror."

London Mayor Sadiq Khan tweeted his response.

Russian President Vladimir Putin wrote a condolence telegram to King Felipe calling for the world to unite in an "uncompromising battle against the forces of terror."

Source: TRTWorld and agencies