An Ohio man accused of plotting with his girlfriend to obtain guns and explosives for a foiled domestic terror attack at a bar was sentenced Tuesday to six years in prison.

Vincent Armstrong, age 24 of Toledo, pled guilty in August to a charge related to conspiring to transport or receive an explosive with intent to harm. Armstrong will remain on probation for three years following his release.

It is believed by prosecutors in the case that Armstrong’s girlfriend, Elizabeth Lecron was the mastermind behind the planned attack and that she introduced him to online communities interested in mass murders.

Prosecutors also said the pair had talked extensively about taking part in violent attacks on public places, visited the site of the Columbine High School massacre and had bomb-making materials and weapons.