[THE INVESTOR] Korean Air Chairman Cho Yang-ho on May 10 quit the top post in budget airliner Jin Air amid ongoing investigations into his family over a series of allegations of physical and verbal violence as well as tax evasion and smuggling.

Jin Air made the announcement in a regulatory filing with the Financial Supervisory Service. The low-cost carrier said Cho's resignation from its CEO post is intended to strengthen a responsible management system by a professional manager.

Korean Air Chairman Cho Yang-ho

Jin Air is the budget unit of Korean Air, the country's No. 1 full-service airline. Both companies are part of Hanjin, a transportation and logistics conglomerate.

Cho's resignation is the latest in a series of moves by Cho's family to try to ease mounting public outrage over allegations of misconduct.

In April, South Korea's customs service raided Korean Air headquarters over suspicions that Cho's family members sneaked luxury goods into South Korea without paying duties.

Police have also launched an investigation into chairman Cho's wife -- Lee Myung-hee -- over alleged physical and verbal abuse. Lee, who is chairperson of the nonprofit Ilwoo Foundation, allegedly tried to slap the face of a construction crew worker hired to remodel her Seoul residence in 2013 while forcing the worker to kneel down. 

By Song Seung-hyun and newswires (ssh@heraldcorp.com)