Defense attorneys for a man accused of killing a University of Illinois scholar from China say they need more time to prepare their case.

Federal public defenders for Brendt Christensen asked a judge Tuesday to push back the trial for the former University of Illinois graduate student to October 2018. Last week prosecutors said they would be ready for trial in late February and argued that the timing should stand unless the Department of Justice chooses to seek the death penalty.

Christensen is charged in the June kidnapping and death of 26-year-old Yingying Zhang. Her body hasn’t been found.

The defense cited the case’s complexity in seeking a delay. The judge has taken the matter under advisement and it’s not known when he will decide.