INDIANAPOLIS (NewsNation Now) — A 17-year-old Indianapolis boy has been charged with murder for allegedly fatally shooting his father, stepmother, two teenage relatives, and a 19-year-old pregnant woman in the family’s home, a prosecutor announced Thursday.

Raymond Ronald Lee Childs III, who was arrested Monday, was charged as an adult with six counts of murder, including one count for the death of the woman’s unborn child, Marion County Prosecutor Ryan Mears announced at a news conference. The baby had been due to be born in one week, he said.

Childs also faces an attempted murder charge in the wounding of another relative, believed to be his brother, who was the sole survivor of Sunday’s shooting at the family’s home on Indianapolis’ near northeast side, authorities said. He was also charged with one count of carrying a handgun without a license.

The elder Raymond Childs, his wife Kezzie Childs, 42, and two other relatives — Elijah Childs, 18, and Rita Childs, 13 — were pronounced dead along with Kiara Hawkins, 19, after being found in the home, the Marion County Coroner’s office said. Hawkins, who Mears said was in a relationship with someone who lived at the home, was first taken to an area hospital, but both she and her unborn male child died despite life-saving efforts, authorities said.

According to court records, the key witness to the horrific violence appears to be the suspect’s younger brother.

Prosecutors believe the 15-year-old boy begged his brother to spare his life while running out of his family’s home. According to the affidavit, the victim pleaded with his older sibling, “I can give you forty dollars, please don’t kill me.”

Despite being shot in the leg and arm, the 15-year-old survived and told police his older brother was responsible for shooting his family.

“It’s horrible. That’s your initial reaction, but then you think what can we do to help,” said Marion County prosecutor Ryan Mears.

Childs’ brother told police that the 17-year-old had gotten in trouble the night before for leaving the house without permission, according to court documents.

The surviving teen recalled hearing his sister yell, “Raymond shot Elijah!” He also told police he heard another gunshot before his father said, “I’m sorry, Raymond. I love you.”

After hearing shots fired in the house, Childs’ brother escaped through a side door. He said Childs chased him down and shot him in the leg and arm. The 15-year-old brother believes Childs intended to shoot him in the head but missed.

Mears claims the violence appears to have started after the suspect got mad at his father, who told the teen he was going to be in trouble for leaving home without permission the night before.

“There’s never going to be a reason to justify what happened.  There’s nothing anyone can say to explain the loss of six lives,” said Mears.

Police found a 9-millimeter handgun and casings inside the home. Investigators also believe the teen used a Draco firearm that was recovered later.

Police spoke with Childs’ girlfriend, who said he’d been at her house on the night of the shooting and had gotten a call from his father telling him to come home. He later came back with two bags of clothes and told her his father had kicked him out, she told police.

The girlfriend then saw neighborhood app alerts about two shootings nearby. Childs denied having knowledge of either shooting, according to court documents.

Later in the morning, the girlfriend went with Childs to an area near the house. She described him as nervous at the scene; at one point he began crying and “acted a clown,” according to court documents. The girlfriend said she “had never seen him like this before.”

Mears said that before the shootings, Raymond Childs III had a dispute with his father, 42-year-old Raymond Childs. “It certainly appears there was an argument between father and son in the residence,” Mears said, adding that police are still investigating the nature of that dispute.

Police found Childs at a relative’s home. He was taken to the homicide office before being arrested, police said.

Indianapolis Police Chief Randal Taylor has said that the deadly shootings were the largest mass casualty shooting in the city in more than a decade and represented “a different kind of evil” than the violent, drug-related crimes and “violence driven by poverty or desperation” that often results in killings.

Although Raymond Childs III is a juvenile because he is 17, he was charged as an adult because state law specifies that any individual at least 16 years of age will be charged as an adult if they are accused of committing certain felonies, including murder and attempted murder. Because the suspect is 17-years-old, prosecutors cannot seek the death penalty.

NewsNation affiliate WXN and the Associated Press contributed to this report.