A man who allegedly killed his wife while his terrified children listened and later claimed she face-planted on the stairs has been arrested.

Spencer Jay Moen, 31, was detained and charged with murder and contributing to the deprivation or delinquency of a minor after police found his wife Sonja Moen, 30, dead on Thursday, 10th August.

Moen had reportedly called 911 at the 1100 block of Eaglewood Avenue in the city of West Fargo, North Dakota State, USA, over Sonja’s death at around 7.39am.

The police who rushed to the scene upon receiving the call were reportedly stunned to find the 30-year-old woman lying fully clothed in a bathtub neither breathing nor responding.

When asked the 31-year-old man first claimed that she had slept in the bathtub the previous night, but was not aware she was unresponsive.

A police affidavit said: “He said she had slept there because she had said she was going to take a bath or a shower. He also said she had vomited last night as well.”

Police officers then spotted visible injuries all over Sonja’s body, including what appeared to be defensive wounds, in addition to having found blood on the master bedroom floor.

When questioned at the police department Moen said both he and his wife had been intoxicated the previous evening.

Police said: “When asked about the injuries to Sonja’s face, Spencer explained that when they arrived home from Mapleton, Sonja had tripped coming up the steps from the garage into the house and ‘face planted’.”

He later explained that after having put the children to bed, the pair had an argument resulting in his wife hitting him in the back of his head and jumping on him while he was in bed.

She then reportedly went to take a shower, reports claimed.

Police said: “Spencer was asked if it would be fair to say that Sonja had fallen in the tub due to the head trauma, associated to the intentional punches. Spencer stated, ‘Sure.'”

The 31-year-old man then claimed he saw his wife lying in the bathtub alive and making noises, before returning to bed.

He had reportedly found her unconscious in the same position the next morning and rushed the children to the daycare before calling the emergency services.

When quizzed one of the pair’s three children claimed they witnessed Sonja’s blood on their father’s face while they were wrestling.

The victim’s eldest daughter reportedly called her the same night at around 10.41pm when Moen answered and told her to go to bed as it was late.

Police said that it turned out that Sonja Moen’s eldest daughter called her the night of Aug. 9. Spencer Moen picked up at 10:41 p.m., however.

Police said: “Spencer’s daughter advised she heard Sonja in the background snoring.”

The 31-year-old man reportedly denied the conversation had taken place.

However, a video found on his iPhone showed Sonja lying in the bathtub in the opposite direction from where she was found by officers at around 11.37pm the night before.

Cops determined that Sonja appears to be agonal breathing in the video – laboured breathing associated with agony or dying – as Moen does nothing to help her while filming.

An autopsy confirmed the victim had suffered a subdural hematoma and died from a blunt force trauma to the head, in addition to having sustained a fractured rib.

Following the incident, Moen was booked at the Cass County Jail for a count of murder and contributing to the deprivation or delinquency of a minor.

His next hearing in the case is scheduled for Wednesday, 20th September.

West Fargo Police Department Chief Denis Otterness said in a statement obtained by Newsflash: “I want to assure the residents of West Fargo that this is an isolated incident and there is no further threat to the public.

“Our department extends its deepest condolences to the family and friends of the victim.”