Hungarian police say 17 suspects have been identified in an investigation into the activities of the Hungarian National Front, a marginal ultra-nationalist group.

Police Lt. Col. Andras Opauszki said Friday that hidden caches of weapons, ammunition, grenades and explosives were also found during the probe, which lasted over two years.

Most of the suspects are believed to have been preparing for violent acts. Three are confined to their homes, while the others aren't in custody.

Opauszki said the group's website included appeals to fight against migrants. Police have handed over the results of their investigation to prosecutors, proposing that charges be brought against the suspects.

Also on Friday, prosecutors charged the former leader of the extremist group, Istvan Gyorkos, in the October 2016 killing of a police officer.