A failed Republican candidate was arrested after he mailed both a pipe bomb that injured a pregnant postal worker and a threatening letter with a bullet inside, according to the FBI.

Eric. P. Krieg, 45, of Munster, Ind,. was arrested Thursday and charged with knowing possession of a destructive device and transporting explosive materials, said U.S. Attorney Thomas Kirsch.

Krieg, an engineer who ran for Lake County councilman and surveyor, maintained a political blog which he used to slam the Lake County Democratic Party and Hammond Mayor Thomas McDermott Jr., according to the Northwest Indiana Times.