A father in Illinois is suspected of killing his small children and himself in a horrific murder-suicide.

CBS News reports that two little boys and their father were found dead after a house fire in Bloomington on Tuesday. The infant and toddler boys had been strangled and their father, Eric Ringenberg, was found dead by hanging in the basement with his son’s bodies.

The mother of the two boys,  Pamela Ringenberg, 32, survived the fire but suffered from smoke inhalation and is hospitalized.

Security camera footage in the home reportedly shows the father hiding cell phones in a kitchen cabinet before setting his home on fire.

The footage, which has not been released, also reportedly shows Pamela waking up to realize her home is burning and searching in vain for phones to call for help. The footage also reportedly shows her frantically searching the home, presumably for her family, but she cannot find them. At that point, her husband and sons would have been dead in the basement.

Pamela escaped the home and got help from neighbors.

A medical examination reportedly found that both boys, a 2-year-old and an infant, were found dead of strangulation by ligature, which is the act of strangling someone with an object but not suspending them.

Investigators have determined that Eric Ringenberg acted alone in the deaths of his sons and in setting the house on fire. The boys have not been identified beyond their initials, CR and RR.

Police have not yet released a motive for the apparent murder-suicide.

Feature photo: People video screenshot