Complex sentence: H.H. Kung's son David was arrested, the Kung's responded by blackmailing the Chiang's, threatening to release information about them, eventually he was freed after negotiations, and Chiang Ching-kuo resigned, ending the terror on the Shanghainese merchants.
Split into simpler sentences: H.H. Kung's son David was arrested, and the Kungs responded by blackmailing the Chiangs, threatening to release information about them. He was eventually freed after negotiations, and Chiang Ching-kuo resigned, ending the terror on the Shanghainese merchants.