The public prosecutor issued search warrants for residences in eastern Luxembourg as a result of the violent demonstrations which broke out in the capital over the last two weekends.
Last week police identified a person present at the anti-Covid restrictions protest who was suspected of having thrown fireworks at officers, the public prosecutor's office announced in a statement on Saturday.
As a result, on Saturday morning police launched a search in eastern Luxembourg, where special police units seized a large amount of explosives, weapons and munitions at a residence in Grevenmacher.
The army and a bomb disposal unit were drafted in to assist with the operation. Officers set up a safety perimeter and evacuated a number of neighbouring residents.
The anti-terrorism unit of the judicial police has launched an investigation, while the suspect, a 30-year-old man, will be brought before magistrates on Saturday afternoon.