• Leaders in the healthcare industry were shocked by the death of UnitedHealthcare CEO Brian Thompson.
• Healthcare leaders shared their condolences in the hours after he was killed.
• "The country lost a leader committed to improving patient care," one CEO wrote.

The killing of UnitedHealthcare CEO Brian Thompson sent shockwaves through the healthcare industry.

Thompson, a 20-year veteran of the company, was fatally shot Wednesday morning on his way to an investor conference for the UnitedHealth Group, the parent company of UnitedHealthcare. The meeting was called off as attendees grappled with the tragic news.

Update: Police have arrested a person of interest in Thompson's killing, 26-year-old Luigi Mangione.

UnitedHealth Group is the largest healthcare carrier in the US, but its competitors came together Wednesday, along with countless peers of Thompson's, to reflect on the industry leader.

"I find myself at a loss for words to appropriately articulate the depth of our feelings for the loss of Brian," Antonio Toft, UnitedHealth Group's vice president of people, culture, experience, and diversity, equity, and inclusion, said in a LinkedIn post. "He was not only a remarkable leader but also a cherished friend and mentor to many of us."

Toft added: "Brian was a true champion for our people and the community, and his impact will continue to inspire us all."

Here's what other health companies and their leaders said about Thompson.

Michael J. Alkire, president and CEO of Premier

"When UnitedHealthcare CEO Brian Thompson's life was tragically taken in Manhattan this morning, the country lost a leader committed to improving patient care," Michael J. Alkire wrote in a LinkedIn post. "Even more tragic, Brian's family lost a father, a son and a brother. I can't imagine their anguish.

"The entire Premier Inc. team and I offer our deepest, most heartfelt condolences to Brian's loved ones and colleagues.

"To honor Brian's memory, we must continue to come together and innovate to improve patient care. That's the legacy he created over two decades in healthcare."

Maria Ghazal, president and CEO of Healthcare Leadership Council

"As a dedicated leader in our industry for over two decades, Brian worked tirelessly to advance healthcare delivery and access for millions of Americans," Maria Ghazal wrote in a LinkedIn post. "His sudden and senseless death is felt deeply by us all."

Rob Davis, CEO of Merck & Co.

"I am saddened to hear about the tragic loss of Brian Thompson, CEO of UnitedHealthcare. His leadership and dedication made a meaningful impact on the health care community. My thoughts are with the Thompson family and all those who worked alongside him," Rob Davis wrote in a LinkedIn post.

Don Antonucci, president and CEO of Providence Health Plan

"Violence has no place in our society, and its presence in our healthcare community is particularly devastating," Don Antonucci wrote in a LinkedIn post. "To our colleagues at UnitedHealthcare — our entire Providence Health Plan family stands with you during this unimaginably difficult time. Our hearts are with Brian's family, friends, and the entire UnitedHealthcare team."

Justin Lake, healthcare analyst with Wolfe Research

"I can literally say that not only myself but my family is better off for having known Brian Thompson and I know from the outpouring of emotion and profound loss today from colleagues across the Wall Street and healthcare communities that there are many, many more who feel exactly the same way," a note from Justin Lake said, according to Bloomberg.

"Most of us sit in jobs where we are fortunate to work with intelligent and thoughtful colleagues on a daily basis, but the relationships we all value and treasure most are with those where the business or investing acumen is combined with character, integrity, kindness and good humor," he also said. "These are the people you feel fortunate to simply interact with much less count as a friend and while I can say my little corner of HC Services certainly has a long list of these types, Brian sat at or near the top for everyone that knew him."

Kaiser Permanente

"Many of us have worked with and known Brian well over the years, and this devastating loss will be felt by all who knew him," a spokesperson for Kaiser Permanente told Business Insider.

Health Care Service Corp.

The company told BI in a statement that Thompson "was a respected leader focused on expanding access to critical health care."

Elevance Health

In a statement to BI, Gail Boudreaux, the president and CEO of Elevance Health, called Thompson's killing a "senseless act of violence," adding: "Leadership in healthcare is marked by dedication, compassion, and a profound commitment to improving lives, and Brian embodied these qualities and more."

David Ricks, chair and CEO of Eli Lilly and Co.

David Ricks was asked about Thompson's death during Wednesday's DealBook Summit. He later shared a LinkedIn post saying that Thompson "was an industry leader and a good partner to Lilly. Our thoughts and prayers are with his family and the entire UnitedHealthcare team."

Humana

"We are shocked and saddened by the tragic death of Brian Thompson, CEO of UnitedHealthcare," Mark Taylor, director of corporate communications at Humana, said in a statement given to BI. "Brian was a visionary leader in our industry, and his loss will be felt for years to come. Our thoughts and sincerest condolences are with his family, friends, and colleagues at this difficult time."