Complex sentence: During a service rehearsal, Gershkovitch removed a man causing numerous interruptions--as a result, Gershkovitch was commanded to visit the Cheka, the presiding chief of which was the victim of the previous day's incident.
Split into simpler sentences: During a service rehearsal, Gershkovitch removed a man causing numerous interruptions. As a result, Gershkovitch was commanded to visit the Cheka, the presiding chief of which was the victim of the previous day's incident.