BOULDER COUNTY, Colo. (KDVR) — The ex-girlfriend of the Longmont postal worker who was murdered last week appeared in court on Tuesday morning.

Devan Schreiner will be held without bail. Schreiner is facing a first-degree murder charge in the death of Jason Schaefer.

Schreiner’s mugshot was released on Oct. 19 by the Boulder County Sheriff’s Office.

Court records show a battle had been brewing between Schreiner and Schaefer.

“Jason had filed documents to have parenting time modified” two days before the shooting, the arrest affidavit states.

“Devan was supposed to be served with the papers,” investigators said in the affidavit.

Investigators were told Devan had threatened Jason.

The two had worked together at the Longmont post office, but Schreiner was fired two weeks ago and began working as a mail carrier in Loveland.

She was on duty the day of the shooting, but her mail truck was not moved for hours.

Schreiner’s next court appearance is scheduled for January.