Andrew Witty, insurance giant UnitedHealth’s CEO, suddenly announced his decision to step down on Tuesday. He will be replaced by Stephen J Hemsley, who served as CEO from 2006 to 2017 and is now returning to the role, the company said in a statement carried by NBC News. Witty will serve as senior advisor to Hemsley, the statement further said. The change comes months after the fatal shooting of Brian Thompson, the UnitedHealth CEO, outside a hotel in New York in December.

Along with the resignation, the company also suspended its annual forecast on Tuesday due to surging medical costs, causing shares to plunge by 18%, a four-year low, as per news agency Reuters.

Witty is leaving due to “personal reasons”, UnitedHealth said without elaborating. His exit comes only a few weeks after UnitedHealth cut its annual forecast and reported its first earnings miss since the 2008 financial crisis, marking a major setback under Witty’s leadership.

The company has been facing sharp criticism over the heath insurance sector’s practices. It has also been investigated by the US Justice Department, NBC News said.

UnitedHealth, however, said in the statement that its “expects to return to growth in 2026”.

Brian Thompson Case Update

Luigi Mangione, who was arrested five days after former UnitedHealth CEO’s death, has urged a judge to throw out his state murder charges in the killing. He faces federal and state charges in New York and Pennsylvania in connection with the shooting.

If that doesn’t happen, they want terrorism charges dismissed and prosecutors barred from using evidence collected during Mangione’s arrest last December, including a 9 mm handgun, ammunition and a notebook in which authorities say he described his intent to “wack” an insurance executive.