An explosion which left one person dead at a house in a Spanish coastal town has been linked to the Barcelona terror attack, police chief Josep Lluís Trapero told a news conference.

Seven people were injured in the blast, which completely destroyed the house in Alcanar, about 126 miles (202km) south of the city, late on Wednesday night.

According to Spanish newspaper El Pais [in Spanish], external, bottles filled with propane and butane were found at the site.

Catalan police have said that neither of the two men arrested is thought to be the van's driver.

They also confirmed another man who ran over two police officers at a police checkpoint has been shot dead, but said there was no evidence to prove this was related to Barcelona terror attack.

At a news conference, a Catalan government official has confirmed the number of injured is more than one hundred.

They also warned the death toll may rise above the 13 already confirmed.

• 13 people have died after a van rammed into pedestrians in Barcelona
• 80 people have been injured: 15 are in serious condition.
• 42 people are described as having 'mild injuries'

• Police say the incident is being treated as a terrorist attack
• Two people have been arrested with reports of another suspect killed in a shootout

The Catalan Red Cross tweeted that they are giving out water and helping people stuck at hotels in the area get home.

The Spanish football league La Liga is to hold a minute's silence in tribute to the victims of the attack.

Catalan President Carles Puigdemont has declared three days of mourning for the region, says the regional government.

Local police also asked people not to share images of the scene on social media.

Footage shows officers searching Barcelona on foot after a van ploughed into crowds.

Tourist Scott Strudwick is on holiday with his family in Barcelona.

Footage shows a vehicle on Las Ramblas moments after it was driven into crowds in Barcelona.

People are queuing up at Barcelona's hospitals to give blood in order to help those who have been injured in the terror attack.

Authorities said at an earlier news conference that 80 people have been injured.

Image source, @TienesTipex

A photo shows a damaged van, believed to be the one used in the attack, surrounded by police officers in the Las Ramblas area of Barcelona.

Image source, Getty Images

Russian President Vladimir Putin has expressed condolences to Spanish King Felipe VI over the attack in Barcelona, the Kremlin's press service reports.

"We resolutely condemn this cruel and cynical crime committed against civilians.

"What has happened once again confirms the need for a real unification of efforts of the entire world community in an uncompromising struggle against the forces of terror," he said in a telegram of condolences, external.

Belgium's deputy PM confirms a Belgian man is among the 13 victims of the Barcelona attack, offering his condolences to the family on Twitter., external

Catalonia's regional head has vowed to "vanquish terrorism" as he thanked emergency services.

Carles Puigdemont also thanked the people of Barcelona and others around the world who offered their support in the wake of the terror attack.

"Catalonia is and has always been a peaceful land where other people are welcome," he told the news conference, held hours after a van ploughed through a crowd in Barcelona.

"Catalonia will always prevail in the face of terrorism," he added. "We will always be united.

"Democracy will always win against barbarism."

Barcelona's mayor, Ada Colau, said the city would hold a minute's silence on Friday at midday.

So-called Islamic State (IS) has claimed responsibility for the Barcelona attack, saying it was carried out by "Islamic State soldiers".

The claim has been made by the IS-linked news agency Amaq. The group gave no evidence or further details to back this claim.