Two men have been charged in the violent mugging-turned-murder of University of North Carolina Chapel Hill pharmacy professor Feng Liu. Liu was an internationally renown scientist whose research specialized on using nanotechnology for drug delivery systems, especially for cancer drugs.

With the story are Anne Blythe and Tammy Grubb of the Charlotte Observer:

UNC professor killed in Chapel Hill; 2 men charged

Feng Liu had a lunchtime routine that his colleagues and lab partners at the UNC-Chapel Hill school of pharmacy knew well.

The 59-year-old Durham resident usually had a bite to eat and left his lab for a brisk 30-minute walk on campus or through nearby Chapel Hill neighborhoods. Typically, he returned cheerful and invigorated by the midday exercise.

On Wednesday, the research professor at UNC’s Eshelman School of Pharmacy never came back.

Chapel Hill police said Liu suffered a severe head injury during a robbery at the intersection of Ransom Street and West University Drive about 1 p.m. Wednesday. Prosecutors said during a brief court hearing Thursday afternoon that the two men who robbed Liu hit him in the head with a rock.

The internationally known scientist died early Thursday morning, leaving a college campus grappling with grief, a sense of unease and numerous questions about how such violence could occur in broad daylight in such a tranquil neighborhood.

“I am heartbroken over this horrible tragedy,” Chancellor Carol Folt said in a statement. “I want to assure you that safety and security of students, faculty, staff and visitors on Carolina’s campus and in the surrounding community is my highest priority.”