Why did An Changlin kill An Xin's parents?

The Knockout An Changlin killed An Xin's parents for his own selfish desires.

An Xin was brought up by Meng Dehai and An Changlin, while An Xin's biological father died in the line of duty when he was young. Meng Dehai and An Changlin never told An Xin why his real father died in the line of duty, let alone the story about his father. An Xin's father is like a fog.

At the beginning, in order to do real estate business in Jinghai, he often used violent means to buy and sell, and even privately formed gangs to clean up disobedient people for him.

Brief introduction to The Knockout's story:

The Knockout TV series is produced by iQiyi and Bai Liu Film and Television, directed by the Central Political and Legal Publicity and Education Bureau and the Political and Legal Comprehensive Information Center of the Central Political Commissar, directed by Xu Jizhou, starring Zhang Yi, Zhang Songwen, whitehairpin and Zhang Zhijian, specially invited by Han Tongsheng, starring Wu Jian and Hao Ping, and starring Gao Ye, Jia Bing and Li Jian.

The play is a chronicle of the rise of evil forces, detailing the escalation of the illegal growth of black malignant tumors. It is a memoir of a resolute struggle against evil, showing the black-and-white struggle and complex human nature under the changes of the times with a panoramic picture narrative spanning 20 years.