BRUSSELS, April 24 (Xinhua) -- European Commission President Jean-Claude Juncker on Tuesday mourned the victims of the van attack in Toronto.

"It is with shock and sorrow that I learnt of the tragic attack in Toronto on Monday afternoon. I send my deepest condolences to the families and loved ones of the victims, as well as to Prime Minister Trudeau and to all Canadians," Juncker said in a statement.

Juncker paid tribute to "the heroic first responders whose calm and courage resolved the standoff without a single shot being fired," underlining that "their actions undoubtedly saved many more lives and we all owe them a debt of gratitude."

The president vowed that the EU "stands with the great city of Toronto and we will put any and all means at the disposal of the Canadian authorities should ever this be needed."

Ten people were killed and 15 others injured after a driver plowed a white rented van into a lunch-hour crowd on a sidewalk in Toronto on Monday in what was described by police as a deliberate attack.

The incident - which Prime Minister Justin Trudeau called a "tragic and senseless attack" - was one of the most violent attacks in recent Canadian history.

Toronto Police Chief Mark Saunders said a suspect identified as Alek Minassian, a 25-year-old from the Toronto suburb, has been detained.

However, the motive of the attack is still unknown and Toronto police have no file record on this suspect, the police chief added. Canada's public safety minister Ralph Goodale is reported to have said there "would appear to be no national security connections".

The incident occurred about 29 km from the city center, where foreign ministers from the G7 countries were meeting to discuss world issues.