Complex sentence: After a meeting with a resistance member he was abducted and interrogated, and sentenced to die by poisoning; he refused to drink the poison and was killed with a neck shot, and his body dumped in the Keizersgracht.
Split into simpler sentences: After a meeting with a resistance member he was abducted and interrogated, and sentenced to die by poisoning. Either he refused to drink the poison or it had no effect and consequently he was despatched with a shot to the neck, his body dumped in the Keizersgracht.