Complex sentence: In 1903 Gershuni and the SR Combat Organisation arranged to assassinate N. M. Bogdanorich, the Governer of Ufa, but Gershuni was unaware that Evno Azef, his deputy was working as an Okhrana spy.
Split into simpler sentences: In 1903 Gershuni and the SR Combat Organisation arranged to assassinate N. M. Bogdanorich, the Governer of Ufa. Though while doing so Gershuni was unaware that Evno Azef, his deputy was working as an Okhrana spy.