Pregnant mom found dead was killed by her boyfriend, who tried to set fire to the home while their 3-year-old daughter watched it happen: Police

Background: News footage of the scene in Milwaukee, Wis., on Jan. 5 (WISN). Inset: Gladys Johnson (GoFundMe).

A Wisconsin woman who was pregnant with her second child and found dead after a house fire was killed by her boyfriend, police said.

Local ABC affiliate WISN reported that Milwaukee police arrested a 21-year-old man in connection with the death of 22-year-old Gladys Johnson, who was found dead in her home on Monday night. The name of the suspect was not released because he has not been formally charged, but police said that the suspect was Johnson's estranged boyfriend and the father of her 3-year-old daughter and unborn son. Police noted that while the man did not have a criminal record in Wisconsin, the couple had a history of domestic violence.

Police said they responded to the Milwaukee home where Johnson lived with her family around 11:30 p.m. on Monday. Gladys Johnson's mother, Michelle Johnson, told local news outlets that she smelled smoke inside the home. She told local Fox affiliate WITI that her daughter's boyfriend would not let her in her daughter's bedroom, "blocking the door, like 'No, you [are] not getting in here.'" He then allegedly pointed his gun at Michelle Johnson's other daughter before fleeing the home.

Michelle Johnson made her way into the bedroom, where she was able to put out the fire and get her unresponsive daughter away from the flames.

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The Milwaukee County Medical Examiner pronounced Gladys Johnson dead at the scene. A cause of death was not provided, but the medical examiner stated that she "may have sustained traumatic injuries following an assault from her significant other." Her death was ruled a homicide.

Gladys Johnson's family members said she was five months pregnant when she was killed. Authorities said the couple's 3-year-old daughter may have witnessed what happened to her mother.

Police said the suspect was found and arrested less than 30 minutes after Gladys Johnson's mother called 911. He faces charges of first-degree intentional homicide and arson. He is currently in custody.