This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

NOBLESVILLE, Ind. – The Hamilton County Sheriff’s Office is investigating the deaths of three family members found in a Noblesville home as a double murder-suicide.

Sheriff Mark Bowen said a press conference Wednesday that he believes 48-year-old Todd Moon shot and killed his parents, 84-year-old Donald Moon and 81-year-old Joyce Moon, before taking his own life on Christmas Day.

The county coroner said the parents died from multiple gunshot wounds, while Todd died from a single gunshot wound to the head.

“This really comes a surprise to many people. Obviously, his family and to us as well,” Sheriff Bowen said.

Sheriff Bowen said Todd called his sister to pick up his 8-year-old twins from the home in the 11000 block of East 191st Street. When she got there, she reportedly found her brother in a “fit of rage.” She tried to calm Todd down, but was unsuccessful.

Detectives report there appeared to be an argument between Todd and his mother Joyce. The argument escalated to the point where Todd retrieved a handgun and shot his mother, according to the sheriff’s office. He then allegedly went to a back room and started firing at his father.

The sister gathered the children, left the residence and contacted authorities around 4:30 p.m.

As the sister was leaving the home, she heard a final gunshot, which she presumed was Todd taking his own life, according to Sheriff Bowen.

The sheriff’s office says there were no criminal charges in the backgrounds of any of the individuals involved, nor was there a known history of mental illness or domestic violence.

“Nothing really to indicate that there were any issues going on here,” Sheriff Bowen said. “Certainly that’s something we are trying to nail down and identify exactly what sent him over the edge and caused him to do something so horrific on Christmas holiday.”

Detectives don’t believe alcohol or drugs were involved in the incident.

The children are receiving care from the Indiana Department of Child Services and are staying with family members.