Erie, Pennsylvania (WJET/WFXP) -- A gruesome discovery in a residence on Sampson Road in Greene Township.

According to Pennsylvania State Police, a father fatally shot his two young children in his home last night before setting fires within the residence and then killing himself.

What started as a call to respond to a house fire ended up being a murder-suicide-arson.

State police have been on the scene since about 2 p.m. investigating what happened.

According to Pennsylvania State Police, 45-year-old Richard Zimmerman took his shotgun and shot and killed his two kids who were ages 10 and 13.

Zimmerman then started multiple fires within the residence and later fatally shot himself.

One state trooper explained that this incident happened overnight.

"This happened between 6/28/21 and 6/29/21 which would have been yesterday through today, so overnight at some point," said Trooper Cindy Schick, Pennsylvania State Police.

When Zimmerman did not show up for his custody hearing on June 29th, a concerned family member arrived at the residence around 2 p.m. and saw smoke coming from the house.

"When the family member arrived at the scene they observed heavy smoke within the residence. Kuhl House Fire Department responded to the scene while extinguishing multiple flames within the residence. Fire fighters observed multiple victims in various rooms of the residence," said Trooper Schick.

Firefighters right away contacted Pennsylvania State Police. The investigators obtained a search warrant to investigate what happened.

When investigators went inside, they made a gruesome discovery.

"Through the preliminary investigation it has been determined that Zimmer inflicted fatal injuries on the victims with his personally owned shotgun. After both victims were deceased, he started multiple fires within the residence and fatally shot himself," said Trooper Schick.

The investigation is still ongoing.

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