Police raided the homes of several Dashnaktsutyun members suspected of plotting a coup early on Thursday, detaining seven people, the Investigative Committee said.
Investigators found an electric detonator, a grenade, a grenade fuse and powder, among other suspicious items, the committee said. The party argued that the grenade was a game prop and that no illegal weapons were seized.
Dashnaktsutyun, one of Armenia's oldest political parties, was founded in Tiflis in 1890. It was part of ruling coalition governments under Presidents Robert Kocharyan and Serzh Sargsyan before going into opposition.