Two children allegedly killed by their mother in Colorado died from gunshot wounds, autopsy records show.
Elianna “Ellie” Wentz, 9, and Aden Wentz, 7, were found dead at a property in Colorado Springs on 19 December.
Kimberlee Singler, 35, is facing extradition from the UK after being arrested in London 11 days later.
El Paso County Coroner documents obtained by the BBC show the children also had high levels of doxylamine – which can be used as sleep medication.
Papers show Ellie suffered a gunshot wound to the head and cuts to her neck which caused her death.
Her younger brother Adam was killed by a gunshot to his head, a separate autopsy states, adding he also suffered neck wounds.
According to each report, written by forensic pathologist Dr Megan Kliesner, the children both had “potentially toxic levels of doxylamine detected in femoral blood”.
Doxylamine is an antihistamine medication which is used in the treatment of insomnia and allergies.
“Autopsy and investigation indicate that these injuries were incurred as a result of the deliberate actions of another person,” the report added.
In the last month, US media has reported Ms Singler and her ex-husband, 38-year-old Kevin John Wentz, had been locked in a court battle over custodial issues since December 2018.
BBC News partner CBS reported that in September Ms Singler filed a request for a temporary protection order in El Paso County, alleging her ex-husband had waved a knife at her.
Mr Wentz denied the allegations, and the case is still open.
Then in November 2023, Larimer County Court heard an emergency motion from Ms Singler to restrict parenting time regarding the same allegations about the knife.
The court found there was no imminent threat from Mr Wentz and rescinded the order, according to CBS.
Also in November, the court ordered the children have additional time with their father around Thanksgiving, and again from 16 December until 31 December.
Reports say Ms Singler did not show up to a police station in December to pass the children to their father for that second stretch. Mr Wentz’s attorney then filed an emergency motion for law enforcement assistance – which was granted by the court.
But, in the early hours of 19 December at 00:29 local time the Colorado Springs Police Department said it responded to a 911 call reporting a burglary inside a condo.
Officers discovered Ellie and Aden had been killed; while Ms Singler and another daughter, aged 11, were found injured and received treatment at the scene before being taken to hospital, it said.
The force later determined the initial report of burglary to be “unfounded” and issued a warrant for Ms Singler’s arrest on 20 December after she allegedly fled for the UK.
Ms Singler was arrested in Kensington, west London, on 30 December, the UK’s National Crime Agency (NCA) said.
She is due to appear at Westminster Magistrates’ Court on 26 February as she awaits her next extradition hearing.
If Ms Singler’s extradition to the US is approved she will face multiple charges, including two of first-degree murder and another of attempted murder, according to UK court papers.
She is also accused of two counts of class two felony child abuse, one count of class three felony child abuse, and one count of assault.
