Mykola Lebed ( or ; January 11, 1909 – July 18, 1998), also known as Maksym Ruban, Marko or Yevhen Skyrba, was a Ukrainian political activist, Ukrainian nationalist, and guerrilla fighter. He was among those tried, convicted, and imprisoned for the murder of Polish Interior Minister Bronislaw Pieracki, in 1934. The court sentenced him to death, but the state commuted the sentence to life imprisonment. He escaped when the Germans invaded Poland in 1939. As leader of OUN-B he is responsible for the genocide of Poles in Volhynia and Eastern Galicia.