Dsani Badgett (Knox County Sheriff’s Office).

After discovering messages that showed he was cheating on her, a Tennessee woman waited until her boyfriend came home from work and allegedly shot him dead, cops say.

Dsani Badgett, 20, faces a first-degree murder charge in the death of her boyfriend, Stephen Morgan, in Knox County, according to court records. According to a Knox County Sheriff’s Office incident report obtained by local NBC affiliate WBIR and CBS station WVLT, deputies responded to a shooting around 5:40 p.m. Saturday. When they arrived, they found Badgett in the driveway screaming for help.

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Deputies went inside and found Morgan suffering from a gunshot wound to the chest. Paramedics pronounced him dead on the scene. Badgett reportedly told detectives he had been using her phone after he busted his. Morgan had later logged onto his Yahoo account on her phone and she allegedly found out about his reported infidelity when she read his messages.

The defendant allegedly grabbed a gun from their bedroom nightstand and “sat on the couch waiting” for an hour until he returned home from work. When he arrived home, she confronted him. She reportedly told deputies she racked the gun several times to show it was loaded and demanded he “do things regarding the situation of their relationship.”

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“The argument got escalated and Mr. Morgan attempted to grab the gun from Ms. Badgett and at that time Ms. Badgett discharged the firearm, striking Mr. Morgan in the left hand and upper chest chest/armpit area,” detectives reportedly wrote.

Cops arrested Badgett and transported her to the Roger D. Wilson Detention Center, where she remains on a $300,000 bond.