Brussels police detained a man with suspected militant links who was found to be carrying two gas cylinders in his car after he was pulled over on Thursday for running a red light, officials said.
After checks were conducted on the vehicle, prosecutors said that one of the cylinders was empty, and no explosive or mechanism of detonation was found in the car.
An official said national counter-terrorism investigators had not been involved.
The man was not named. Prosecutors said it was too early to speculate on whether he had any criminal intent, although he was “known to police”.
The mayor of the district where he was stopped said police had previously suspected him of links to radical Islam.
With the Belgian capital on high alert approaching the first anniversary of Islamic State suicide attacks that killed 32 people on March 22, an area close to the city’s main Gare du Midi rail station was sealed off and the bomb squad called in to check the car after local officers had pulled the driver over.
The police cordons have now been removed.
Reuters reporters heard two controlled explosions. Prosecutors later confirmed the explosions were executed by the army’s bomb squad.