Children left to play with their own poo while their dad sexually abused their four-year-old sister have been rescued from a trailer home in Oklahoma.

Father Steven Zackariah Kittle, 35, has been charged with neglect and sexually assaulting his daughter even when her one-year-old brother was in the same room at the home in Stillwater, Payne County in the US state of Oklahoma.

A third child – an 18-month-old girl – was found to be deformed, with bugs in her ear canal, according to local media.

The children’s mother Lindsey Nichole Pratt, 26, and their grandmother Robin Jean Kittle, 59, are both facing three counts of child neglect.

Police uncovered the house of horrors when they searched the family home to investigate the sex abuse, which Kittle has admitted to in a police interview.

The trailer was so soaked with human and animal faeces and urine that the officers’ boots stuck to the floor.

And court documents reveal that inside the stench was so unbearable that the investigators had to take breaks outside to stop themselves from gagging.

Bags of food were found hanging from ceilings to stop infestations of rats and cockroaches from eating them.

Sickening stains were smeared all over the walls as the children played with their own poo instead of toys.

And police found the children had been so neglected they could only communicate with grunts.

Stillwater Police Detective Sgt. Sherae LeJeune – who visited the home with a welfare worker – said: “The foul odour inside was unbearable. The air was thick and musty which made breathing difficult.”

She added: “We could not complete the walk-through without taking breaks outside for fresh air.

“I noticed there actually was carpet in the living room.

‘It was saturated with so much urine and faeces and walked all over that it was smashed down to a hard surface. My boots stuck to the flooring.

“It was impossible to avoid stepping in dog faeces throughout the home. There was old and fresh faeces everywhere.

“There were several sticky fly traps hanging from the ceilings which were covered with bugs.

“I noticed there were bags of food hanging from the ceiling as well, which I later learned was to keep rodents and bugs from getting to it.”

The trailer was home to three adults, three children, six dogs and three cats, according to court records.

LeJeune said that a bed in the two eldest children’s bedroom had “exposed nails sticking out of the bed frame”.

She added: “There were no toys in the room. The walls were smeared with faeces.

“It was obvious the children smeared the faeces because of the size of the handprints.

“Some of the smears reached up to the ceiling on the west wall.”

The three children have been taken into care by Oklahoma Department of Human Services.

The pets were handed over to animal welfare, the court documents said.

Court documents say the children could only communicate by “pointing and grunting”.

The affidavit said that the younger girl “had deformities in both legs and a dead roach was removed from her ear canal.”

Lejeune stated: “Steven said he knew his house was a ‘pigsty,’ and they had slacked on cleaning it.

“He acknowledged that the brown spots on the wall were faeces. He described it as ‘caveman drawings’ and said the children play in their faeces a lot.”

Prosecutors say the two oldest children “were confined to their bedroom for 20 hours a day, every day, for the past year”.

They say the children “lacked adequate nurturance, affection, food, sanitary environment and necessary medical attention.”

Dad Kittle is being held on a USD 150,000 (GBP 117,800) bond and faces up to five life sentences if found guilty of all charges.