Two doctors, an employee and a patient were gunned down at a Tulsa, Oklahoma, medical building on Wednesday after the gunman allegedly targeted his doctor, blaming him for pain.
Here is what we know about the four people who died in America's latest mass shooting.
Dr. Preston Phillips, 59
Dr. Preston Phillips was an orthopedic surgeon at Saint Francis Hospital. He had "an interest in spinal surgery, joint reconstruction -- including joint replacement and the treatment of fractures," according to the hospital website. He graduated from Harvard Medical School in 1990 and also earned advanced degrees in organic chemistry and pharmacology, as well as theology from Emory University, police said in a statement on the victims.
Dr. Cliff Robertson, president and CEO of Saint Francis Health System, described Phillips as a "consummate gentleman," telling reporters, "he is a man that we should all strive to emulate."
Phillips was the target of the mass shooting, authorities said.
Phillips performed surgery on the suspected gunman on May 19, Tulsa Police Chief Wendell Franklin said.
The suspect was released from the hospital on May 24, and after his release, he called several times over several days complaining of pain and wanting additional treatment, the chief said.
On Tuesday, Phillips saw the suspect again for additional treatment, the chief said. Then, on Wednesday, the suspect called the doctor complaining of back pain and wanting additional help, the chief said.
A letter found on the gunman, who died by apparent suicide at the medical facility, made it clear "that he came with the intent to kill Dr. Phillips and anyone who got in his way," Franklin said. "He blamed Dr. Phillips for the ongoing pain following the surgery."
Dr. Stephanie Husen, 48
Dr. Stephanie Husen, a sports medicine specialist, was working at the medical office when she was killed.
She graduated medical school at Oklahoma State University in 2000 and completed her internship and residency at Greenville Memorial Hospital, according to her hospital profile.
She completed her undergraduate degree at the University of Oklahoma and was a member of the Chi Omega Sorority.
"Our hearts are with the family and loved ones who lost such an incredible woman," the chapter said in a statement on social media. "She was known and loved by so many and will always be remembered."
Amanda Glenn, 40
Amanda Glenn was an employee who had a "supervisory role" at the medical facility, officials said.
She leaves behind a husband and two teenage sons, The Oklahoman reported, citing her Facebook page.
"Amanda Glenn was a devoted wife, mother and friend," the Sandite High School baseball team posted on Facebook. "She was on our Booster Club Board and served the baseball boys and coaches selflessly. She was the biggest cheerleader for both of her sons and all of our boys."
Glenn worked in the medical field for over 18 years and had a "true servant's heart" in that she "always put everyone else first," the Tulsa police said in their statement on the victims.
William Love, 73
William Love was a patient receiving care when the gunfire erupted.
Officials said Love held a door closed to help someone else escape the shooting. That person appears to be his wife of nearly 55 years, Deborah Love, according to a police statement.
"William Love's family would like us to share that at the time of shooting, William heard the gunshots and knew his wife would not be able to escape the building on her own," the Tulsa Police Department said in its statement on the victims. "He sacrificed his life for her."
Love was a retired Army first sergeant with 27 years of service who served one tour in Vietnam, police said.
He is survived by his wife, brother, two daughters and their spouses, eight grandchildren and six great-grandchildren, police said.