India, May 13 -- UnitedHealth Group on Tuesday made a surprising announcement about appointing a new CEO. The sudden move was taken in the wake of the December shooting death of the CEO of its UnitedHealthcare subsidiary.

Stephen J. Hemsley was named the new CEO with immediate effect after Andrew Witty resigned as CEO for "personal reasons."

The firm has been under fire for issues in the insurance sector, and in the last year, its stock price has fallen precipitously.

Hemsley will continue to serve as the chairman of the company's board of directors. He served as the firm CEO from 2006 to 2017. According to a press release from the company, Witty will serve as Hemsley's senior adviser.

According to a statement from UnitedHealth Group,...