Complex sentence: In the summer of 1943 the SD arrested several SOE agents and French resistance fighters, it was soon reported to London by some of the remaining agents, that Déricourt had had regular contact with senior SD officers.
Split into simpler sentences: In the summer of 1943, the SD arrested several SOE agents and French resistance fighters. It was soon reported to London by some of the remaining agents that Déricourt had had regular contact with senior SD officers.