UnitedHealth Group said on Thursday it has appointed Tim Noel, the head of its Medicare business, to replace late CEO Brian Thompson as the head of its insurance unit.

UnitedHealth Group (UNH) announced a new chief executive officer for its health insurance unit, UnitedHealthcare, Thursday, filling the role after Brian Thompson was shot to death last month in New York City.

UnitedHealth reported fourth-quarter results on Thursday that reflected persistent challenges for the health insurance sector.

The company said Thursday that Tim Noel will be CEO of UnitedHealthcare, replacing Brian Thompson, who was killed in New York City in December.

UnitedHealth Group Inc. promoted the head of its Medicare health plan business to lead the company’s broader insurance division, filling the job previously held by slain executive Brian Thompson.

UnitedHealth Group will promote one of its top insurance executives to replace Brian Thompson, the slain CEO of its UnitedHealthcare arm. The company said Thursday that Tim Noel will become the next UnitedHealthcare leader. Noel most recently led UnitedHealthcare’s Medicare and retirement business. He joined the company in 2007.

The health insurance provider has named Tim Noel, the head of its Medicare business, to take over from Brian Thompson.

UnitedHealth Group (NYSE:UNH), a leading diversified healthcare company with a substantial market capitalization of $469.7 billion, continues to navigate a complex landscape of opportunities and challenges as it maintains its position as a dominant force in the healthcare industry.

In his first public remarks since the murder of UnitedHealthcare CEO Brian Thompson last month and the backlash against the insurance industry it provoked, Witty said the healthcare conglomerate is looking for ways to simplify and accelerate its prior authorization processes. He did not offer specifics.

UnitedHealth Group beat estimates for fourth quarter profit as the Eden Prairie-based health care giant released its first earnings report since the fatal ambush last month of top executive Brian Thompson in New York City.

In his first public comments since one of his executives was shot to death, UnitedHealth Group CEO Andrew Witty said the healthcare system “needs to function better.”