Complex sentence: Ptolemy thereupon sent a large force against Cyrene under Ophellas, to whom the exiles, who had taken refuge with Thimbron, endeavoured to escape, but were detected, and put to death.
Split into simpler sentences: Ptolemy thereupon sent a large force against Cyrene under Ophellas. The exiles who had taken refuge with Thimbron, endeavoured to escape and join Ophellas, but were detected and put to death.