In the aftermath of a suspected plot by a far-right group to forcibly topple the government and install a minor royal as head of state, Germany intends to strengthen its gun rules, its interior minister said in an interview published on Sunday.

The conspiracy, which has horrified many in one of Europe’s most stable democracies, has resulted in the arrests of 25 individuals by German police last week.

According to authorities, several of the accused were members of the far-right “Reichsbuerger” (Citizens of the Reich) movement, which opposes the existence of the current German state.

In an interview with the “Bild am Sonntag” newspaper, Interior Minister Nancy Faeser warned that the Reichsbuerger posed a growing threat to Germany, as its population had increased from 2,000 to 23,000 over the past year.

Faeser was cited as saying, “These are not harmless lunatics waiting in pre-trial jail; these are terrorism suspects.”

Prosecutors have stated that some of the accused have guns and knew how to use them. They attempted to recruit current and former military personnel and stocked up on weaponry.

Faeser was cited as adding, “We need all authorities to exert maximum pressure” to take their firearms, which is why the government will “shortly further tighten gun restrictions.”

Before the attacks, more than one thousand Reichsbuerger members had already been disarmed. In a country where private firearm ownership is uncommon, it is thought that at least 500 individuals still retain gun licenses.