The gunman who killed 3 people at a Chicago hospital on Monday targeted his former fiancee, a doctor who worked in the hospital's emergency room.
Dr. Tamara O'Neal was gunned down by her former fiancé, 32-year-old Juan Lopez, while walking into the hospital on Monday afternoon.
Witnesses saw Dr. O'Neal and Lopez arguing in the hospital parking lot. When a friend tried to intervene, Lopez lifted his shirt to reveal a handgun.
The friend ran into the hospital to find help, and gunfire rang out seconds later.
Police say Lopez shot O'Neal once, and when she fell to the ground, he stood over and shot several more times.
Lopez then shot and killed Chicago PD Officer Samuel Jimenez and pharmacy resident Dayna Less before turning the gun on himself.
Friends say Dr. O'Neal was "dedicated to her church" and she had "a heart of gold," according to Chicago 5 News.
Colleagues described Dr. O'Neal as a hard worker who was tenacious and stood out among her peers. She showed leadership skills early in her training as a medical student at Southern Illinois University, and she was a volunteer and CPR trainer in Illinois Heart Rescue Project community outreach programs for underserved populations.