Teachers, family testify about killer's descent

Teachers, colleagues and family members of Brendt Christensen, convicted of killing visiting Chinese scholar Zhang Yingying, continued testimony on Thursday at the sentencing phase of his trial at US District Court in Peoria, Illinois, as defense attorneys sought to avert a death sentence for the murderer, a former University of Illinois graduate student.

Christensen, who entered UI as a PhD candidate in physics in 2013 after graduating from the University of Wisconsin-Madison with a bachelor's degree, was motivated when he started his studies but soon ran into intermittent troubles, testified witnesses who knew him at the university on Thursday.

Christensen seemed "very enthusiastic" when he joined a research group in 2014, the group's head Nadya Mason testified, but "it became clear it wasn't working out" in the spring of 2016, according to The News-Gazette of Champaign, Illinois.