(CNN) At a courthouse thousands of miles from his home in China, a father pleaded with a killer to tell him where his daughter's body was last placed.

Brendt Christensen , 30, was sentenced Thursday to life in prison for the kidnapping and killing two years ago of 26-year-old Yingying Zhang , a student at the University of Illinois Urbana Champaign's department of Natural Resources and Environmental Sciences.

Her remains were never found.

"Now that the trial is over, and the jury has made its decision, we ask the defendant to unconditionally tell us what he knows about Yingying's location," her father, Ronggao Zhang, said in Chinese, according to a translator. "If you have any humanity left in your soul, please help end our torment. Please let us bring Yingying home."

The jury could not reach a unanimous verdict on the death penalty, so a judge imposed the life sentence.