A letter containing suspicious white powder was discovered in the offices of State Security, on Boulevard Albert II in Brussels, on Wednesday morning.
Brussels police confirmed the information to the Belga News Agency. Police, fire brigade and civil protection officials were called to the scene earlier in the day set up a perimeter, but have since dispersed.
One person has been quarantined as a precaution.
Peter Gorlé, spokesman for Belgian State Security, said that the suspicious letter was discovered this morning while sorting mail.
"All the procedures laid down for this type of situation were followed, the premises were isolated and the employee who had been in contact with the letter was placed in quarantine and transferred to hospital," he said.
"According to initial information, there is no reason to suspect any contamination. The suspect envelope has been taken in charge by the civil protection for analysis," he added.
