UnitedHealth Group CEO Andrew Witty said the company remains in a “state of mourning” over the shocking death of Brian Thompson, but that it owes it to him to “make health care work better for everybody, in every way.”

In a memo to employees, Witty described Thompson, the CEO of UnitedHealthcare, a UnitedHealth insurance subsidiary, “as one of the smartest guys” and “one of the best guys.”

He vowed that the company would make good on its promise to continue offering quality healthcare to its members.

“No matter what’s happening, we’re going to be there for the moms and dads who brought one of their kids to a clinic this morning,” said Witty. “We’re going to be there for the sickest and the most vulnerable among us, whose homes our nurses and case workers are visiting today.”

“We’re going to make sure medicines are filled, infusions are administered and people can navigate their therapies for the rarest states of disease,” he added. “The same people who were counting on us last week are counting on us today — none of that’s changed. Our patients, our customers, partners and clients need us to be at our very best. And then again tomorrow. The day after next. Next week. Next month. Next year.”

Witty noted that while the past few days “have been dark, our patients, members, customers are sending us light.”