Explosions and gunfire have been heard during ongoing police operations in Brussels, according to eyewitnesses and reports by the Associated Press.
A Belgian state broadcaster has said a major "anti-terror" operation is underway in the Shaerbeek neighborhood, with one suspect reportedly "neutralized."
The area has been closed off and a tram was evacuated as police and military vehicles were seen in the district.
A witness sighting of a bomb squad and specialist robot sparked speculation that a controlled explosion had occurred during the raid.
Seven people were arrested in overnight raids in Brussels in connection with the Tuesday bombings at Brussels airport and a central metro station.
