BROKEN ARROW, Okla. — The deaths of eight people found in a burning Oklahoma home – including six children ranging in age from 1 to 13 years old – are being investigated as a murder-suicide, with both adults considered suspects, authorities say. 

At a Friday news conference, Broken Arrow Police Chief Brandon Berryhill said first responders found two adults in the front of the house before finding the six juvenile victims. The children were found in one room in the back of the house “where the majority of the fire was contained,” Fire Chief Jeremy Moore said.

“To arrive on scene yesterday and to see the looks on our first responders’ and firefighters’ faces just absolutely broke my heart,” Moore said.

Both adults are suspects and the deaths are being investigated as a murder-suicide, Berryhill said.

Moore said it is not believed any of the victims died from the fire.

“Those injuries did appear to our fire crews at that time immediately to be criminal in nature,” Moore said. “And so we immediately called for the police department to come and intervene on the fire scene.”

Berryhill said firearms were recovered from the home. Sara Abel, a spokeswoman for the Bureau of Alcohol, Tobacco, Firearms and Explosives, said the agency is assisting local police in tracing guns found in the home but she did not have any details about the type or number of firearms. 

The fire was reported about 4 p.m. Thursday in a quiet residential area of Broken Arrow, the largest suburb of Tulsa, with about 115,000 residents.

WHAT WE KNOW:2 adults, 6 children found dead in alleged murder-suicide

Broken Arrow police and fire officials investigate the scene of a house fire with multiple fatalities on Thursday.

The owner of the house said it was being rented by a couple and their six kids, a family neighbors described as mostly secluded, though they would play basketball in the driveway. Police have not yet identified the victims.

The landlord, Kris Welch, said the family had rented the home for eight years.

Crime scene investigators were working Friday morning inside the house, which appeared to have blood stains on the front porch and parts of the front door.

Dusty Creecy lived directly behind the family for over a year and said she would see children playing on the trampoline in the backyard.

“It is very sad because I would see young kids,” Creecy said. “One in diapers for sure.”

The home on the 400 block of South Hickory is in a community with a mix of longtime residents and short-term renters.

Bob Stewart has lived in the neighborhood for 30 years and said the man who lived in the house was known by neighbors to have a gun.

“The guy, he used to walk around with a gun attached to him, even when he was mowing the lawn,” Stewart said.

Contributing: Claire Thornton, USA TODAY; Jana Hayes, Ben Felder and Jessie Christopher Smith, The Oklahoman; The Associated Press.