A Delaware ex-convict was found guilty Thursday in the rape and murder of a college student from White Plains.

Even his attorneys conceded that 36-year-old James Cooke Jr. broke into 20-year-old Lindsey Bonistall?s apartment when she was a sophomore at the University of Delaware in May 2005. However, the defense maintained that Cooke was mentally ill.

Prosecutors called Cooke a cold, calculating killer who knew exactly what he was doing when he strangled Bonistall to death, pointing to his effort to cover up the crime by setting fire to Bonistall?s apartment.

The jury agreed with the prosecution, finding Cooke guilty of rape, first-degree murder and other felonies related to the crime after deliberating for almost three days.

Bonistall?s mother, Kathleen, thanked prosecutors for securing a conviction. ?We're just thankful that justice has prevailed,? she added.

A separate sentencing trial will determine if Cooke will get the death penalty. Related Information Prosecutors may seek death penalty in murder of White Plains student Man arrested for DE burglary may be linked to murder of White Plains student