A Delaware man who beat his girlfriend to death apparently thought she was speaking to a former boyfriend, sending him into a fit of rage.

Delaware.gov reports that 45-year-old Steven Pierce was sentenced to serve life in prison for the death of his girlfriend, 31-year-old Heather Stamper of Delaware City. According to court documents, in July 2016, Pierce waited until Stamper fell asleep, then went to her home and bludgeoned her to death.

The couple was last seen together on Clinton Street in Elsmere. While Stamper went home after a night out, Pierce went to an acquaintance’s home and asked to borrow a gun, claiming he wanted to kill Stamper. The unknown acquaintance didn’t give Pierce a gun, according to Delaware Online.

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Pierce later went to Stamper’s home and was let in by her roommate. The roommate said they heard a loud bang coming from Stamper’s basement room. Around 15 minutes later, Pierce emerged crying and told the roommate that his relationship with Stamper had ended.

“‘We broke up. I’ll never see that [expletive] again,” Stamper said, according to court records.

On July 9, 2016, Delaware City Police and New Castle County Police went to victim’s home off of the 200 block of Adams Street after Pierce called 911 and claimed he found her with her dead with her hands tied. New Castle County Emergency Medical Services arrived to the scene and pronounced Stamper dead.

An autopsy later confirmed that Stamper died of blunt force trauma.

After conducting numerous interviews and collecting evidence, authorities arrested Pierce in October 2016. He remained behind bars on a $2 million bond while awaiting his trial.

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[Feature Photo: Heather Stamper/Facebook]