DAYTON, Ohio – A mother intentionally put her month-old daughter in a microwave oven and cooked the child to death after a fight with her boyfriend, a prosecutor told jurors Thursday.

Defendant China Arnold and her boyfriend had argued over whether he was the biological father, Assistant Montgomery County prosecutor Daniel Brandt said during closing arguments in the woman's retrial. The argument got so heated that Arnold bit her boyfriend's lip and he slapped her, Brandt said.

Arnold, 28, of Dayton, is accused of killing her infant daughter Paris Talley in 2005. She could face the death penalty if convicted of aggravated murder.

Brandt said Arnold told a cellmate she put the baby in the microwave and turned it on because she was worried her boyfriend would leave her if he found out the child wasn't his, Brandt said.

“She could have stopped it with one finger, but she didn't,” Brandt said. “We know she used that microwave as the instrument of death.”

Defense attorney Jon Paul Rion told the jury there was evidence that someone else was responsible.

He cited testimony from a boy who said he saw another boy walk into the kitchen of a nearby apartment with the baby, heard the microwave go on, and then later saw the burned baby in the microwave.

“He told a very believable story,” Rion said.

Jurors deliberated for about four hours Thursday and were expected to resume deliberations Friday.

Judge John Kessler declared a mistrial in February after he privately heard the youngster's account. The boy, now 8, testified at the retrial Tuesday.

In rebuttal, however, the 8-year-old's mother testified Wednesday that they lived some distance away and they were not at Arnold's apartment complex when the baby died. Her former live-in boyfriend also testified that he was certain the boy was not at the location.