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Spanish police said the dead and injured in Thursday's terrorist attack in Barcelona come from 34 countries, including Canada.
Authorities say terrorists spent a long time planning before renting a van and driving into a crowd of people in a pedestrian mall in Barcelona. A short time later people in a speeding car made a similar attack about 100 km west in the resort town of Cambrils.
Police shot and killed five suspects in Cambrils, four others were arrested, and several suspects are at large. One of the suspected terrorists died earlier this week when their base, a home in Alcanar, exploded.
On Friday the king of spain, Felipe VI, and Spanish Prime Minister Mariano Rajoy led a march through the area in Barcelona, known as Las Ramblas, to honour the 13 people who died and the more than 100 who were injured.
Global Affairs Canada is not providing any details about who the imapcted Canadians are or where they are from.
“Our thoughts are with the Canadians who were affected by the terrorist attack that occurred in Barcelona, Spain,” Global Affairs Canada spokesperson Austin Jean told CTV News in an e-mailed statement, confirming that Canadians had been impacted.
“Global Affairs Canada is communicating with local authorities in order to gather additional information and we are in contact with the family members of the affected Canadian citizens in order to provide consular assistance,” Jean said.
Citing privacy reasons, Jean declined to identify the Canadians.
Prime Minister Justin Trudeau said in a statement Thursday that he was "deeply saddened" by the news.
"While we cannot ignore the outrage we feel, together we must renew our commitment to protect the freedom found in societies that promote unity, openness and inclusion," wrote Trudeau, who has been on a family vacation in British Columbia this week.
"Spain, we grieve with you and denounce hate and violence in all of its forms. Canada will continue working with the international community to fight terrorism and build a world where we can all feel safe and secure."
In Quebec, flags are flying at half-mast throughout the province to honour those slain.
Premier Philippe Couillard called the attacks horrible, and said it was a sign the world must reject "blind violence and terrorism."
"We have to continue together, together, us and Canada with our allies to fight terrorism, prevent it as well, and this is what we need to do. And each time this type of horror will happen we condemn it, but also we'll keep acting on it through fighting, yes, but also prevention," said Couillard.
CAQ leader Francois Legault, who was in Barcelona earlier this summer, said the attacks were "appalling."
PQ leader Jean-Francois Lisée said he was horrified, and stood in solidarity with Spain.
Meanwhile Montrealers with ties to Spain said they were surprised by the attacks, but that they were not afraid of more terrorist assaults.
The Canadian government is also urging travellers to avoid the Las Ramblas area. Canadians requiring consular assistance in Barcelona are being asked to call +34 93 270 3614, +1 613 996 8885 or email sos@international.gc.ca.
With a report from CTVNews.ca