A medical researcher said to be on the "verge of making very significant" coronavirus findings was found shot to death over the weekend in Pennsylvania, officials said.
Bing Liu, 37, a researcher at the University of Pittsburgh School of Medicine, was found dead Saturday inside a home in Ross Township, north of Pittsburgh, the Allegheny County medical examiner said.
He had been shot in the head and the neck, the agency said.
An hour after Liu's body was discovered, a second person, Hao Gu, 46, was found dead inside a car less than a mile away, the agency said.
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Ross Township police Detective Sgt. Brian Kohlhepp told NBC News that the men knew each other. Investigators believe Gu killed Liu before returning to his car, where he died of a self-inflicted gunshot wound.
Police believe the deaths occurred on Saturday after a "lengthy dispute regarding an intimate partner," according to the Ross Police Department Wednesday.
"We have found zero evidence that this tragic event has anything to do with employment at the University of Pittsburgh, any work being conducted at the University of Pittsburgh and the current health crisis affecting the United States and the world," police said.
The investigation has been forwarded to federal authorities because neither of the men were U.S. citizens.
Liu, who earned a Ph.D. in computational science from the National University of Singapore, worked as a postdoctoral fellow at Carnegie Mellon University before becoming a research associate at the University of Pittsburgh School of Medicine.
In a statement, the University of Pittsburgh described him as an excellent mentor and prolific researcher who had co-authored more than 30 papers. His work focused on systems biology.
"Bing was on the verge of making very significant findings toward understanding the cellular mechanisms that underlie SARS-CoV-2 infection and the cellular basis of the following complications," the school said. "We will make an effort to complete what he started in an effort to pay homage to his scientific excellence."