A view of the street scene after people were killed when a truck crashed into a department store Ahlens, in central Stockholm, Sweden, April 7, 2017. [Photo/Agencies]

PARIS - A truck attack in a shopping street in central Stockholm on Friday showed that "relentless fight against terrorism must be a priority of European solidarity," said French President Francois Hollande.

Expressing "dismay and indignation," Hollande sent sympathy and solidarity message to families' victims.

In a joint statement with his German counterpart Sigmar Gabriel, French Foreign Minister Jean-Marc Ayrault said they were "distressed by the fact that Sweden may have been the victim of such an act of terrorism."

"In these difficult times, we stand alongside our Swedish friends. We hope that all the light will be be shed on this horrible act," they added.

Earlier on Friday, a truck crashed into a crowd on a shopping street and a department store in central Stockholm, killing at least four people and wounding many others in a likely terrorist attack, according to Swedish officials.

The incident came just two weeks after a man drove a car into the crowded Westminster Bridge in London, killing four, and then stabbed a policeman to death before being shot dead by police.

The recent attacks in main European capitals reminded people of Nice attack last summer when a 31-year-old delivery man drove his heavy truck into revellers of Bastille Day in French Rivera city of Nice, leaving 86 people killed. The Islamic State claimed responsibility for the attack.