Nebraska prosecutors have raised the charge against a Texas man to first-degree murder.

Forty-seven-year-old Craig Johnson, of Lovelady, Texas, already had pleaded not guilty to a charge of second-degree murder. Prosecutors say he killed his girlfriend, 42-year-old April Smith, on Dec. 11, 2011, at the home they shared eight miles west of Sidney in the Nebraska Panhandle.

Cheyenne County Attorney Paul Schaub says new information obtained by investigators convinced him that Johnson’s was a first-degree murder case.

Authorities say Johnson became enraged at Smith because she’d let her estranged husband to fix her vehicle. People also reported to police that Smith planned to reconcile with her husband.

A trial date hasn’t been set.