A van ploughed into a cafe terrace in central Brussels on Friday afternoon, leaving six people with minor injuries, according to Belgian police.
One suspect -- whose motivates "are not known" as of Friday evening -- was arrested shortly after the incident, which took place at around 13:00 local time on Rue Saint-Michel, near the city's shopping district.
It's unclear at this stage whether it was a deliberate act or an accident.
A spokesperson for the city's public prosecutor's office refused to give any information on the profile of the arrested person.
"The investigation is still ongoing to clarify the exact circumstances of the facts," said Willemien Baert at a press conference. "At this stage, the various leads are still open, the motives of the suspect are not yet known."
When asked if it could be terror-related, Baert underlined that it was "not yet sure that it is an attack, it is possible that it was just an accident."
Police said the driver of the vehicle fled the scene after the incident, which left two establishments damaged, Le Corbeau and City Pizza.
Emergency services arrived on the scene very quickly and treated six minor injures on the spot, while the van involved in the crash was found shortly after.
The mayor of Brussels told reporters that the vehicle was "travelling at extremely high speeds" towards the terrace, where there was a mix of tourists, city employees and Belgian locals.
Reporting from the scene, Euronews correspondent Méabh Mc Mahon said the shopping district was calm and back to normal later on in the afternoon.