- The man was wearing a winter coat when it was 32 C (90 F)
- Brussels has been on heightened alert since terrorists killed 31 people in March
The man was seen with a wire hanging out of a winter coat while it was 32 degrees Celsius (90 degrees Fahrenheit).
The police operation brought part of Brussels to a standstill. A nearby library was evacuated as police set up a security perimeter.
But after hours of investigation, Brussels police said the man was not a threat -- but rather a student researching radioactivity in the city.
The Belgian capital has been on high alert after terror attacks killed 31 people in March
. Two bombs exploded at the Brussels Airport
, and a third went off at a metro station.
ISIS claimed responsibility for the bombings, which also wounded 300 people.