Emergency services were called to the headquarters of the European Commission in the European Union (EU) after a suspicious white substance was found near the office of President Ursula von der Leyen.
Crews in hazmat suits have been seen outside the Brussels building, though the situation is said to be "under control" and the building is not being evacuated.
The building, known as 'The Berlaymont' houses the European Commisssion, the executive branch of the EU.
A spokesperson for the Brussels Fire Brigade, Walter Derieuw, said only one person came into contact with the unknown substance but has not presented any medical symptoms.
He said: "We are waiting for an initial analysis for the victim. If it is negative, there will be no hospitalization."
Emergency services were called to the 13th floor at around 11:50 local time, according to The Brussels Times, and the incident was originally mistaken for a fire.
The powder is now being analysed by Civil Protection and the room in which it was found is under quarantine.
A medical team is also present and the Mirror has contacted the EU for comment.
von der Leyen, 63, is responsible for setting out the policy of the Commission and took over from Jean-Claude Juncker in 2019.
Presidents are elected for a five-year term and von der Leyen took the role after moving on from a role as Deputy Leader of the Christian Democratic Union in Germany from 2010 to 2019.
Part of the German's role is to represent the EU abroad and as a result, she has been one of the main voices in the organisation advocating for sanctions against Russia for its war in Ukraine.
On Wednesday, she said new sanctions would "make the Kremlin pay" for its invasion and sham annexations of four regions in Ukraine.
She said: "We do not accept the sham referenda and any kind of annexation in Ukraine, and we are determined to make the Kremlin pay for this further escalation."
