The man, believed to be armed with a pistol, a machine gun and a missile launcher, has in the past made threats against Belgium’s most famous virologist, Marc van Ranst.
Van Ranst, an ever-present on national TV during the COVID pandemic, has been moved to a safehouse while police search for the man, who has not been named in line with privacy laws in Belgium.
According to Belgium’s De Standaard, federal prosecutor Eric van Duyse said the wanted man was in his 40s and had received military training.
On Wednesday police were searching woodland close to the Dutch border in Limburg, north Belgium.
"There are indications that he is violent, and in the past 24 hours indications have emerged that the man poses an acute threat," Belgium’s Minister of Justice Vincent Van Quickenborne told local TV.
Writing on Twitter in the early hours of Wednesday morning, Van Ranst said that far-right threats “do not make the slightest impression on me.”