A US mother accused of shooting two of her children at their home in Colorado was “begged” by her third child not to kill her, a UK court has heard.Kimberlee Singler has attended the start of her extradition hearing in London after being accused of murdering her daughter Elianna, 9, and son Aden, 7, who were found dead in their bedroom in Colorado Springs on 19 December last year.The eldest child, aged 11 at the time, survived being stabbed in the neck but needed emergency surgery, Westminster Magistrates’ Court heard.Through her defence barrister Ms Singler, 36, denied responsibility for the deaths and the attack on the third child.Warning: This report contains graphic descriptions of violence against childrenIt will not ultimately be for the London court to carry out a criminal trial.Ms Singler is wanted in Colorado to face a seven-count indictment, comprising two counts of first-degree murder, one count of attempted murder, two counts of class-two felony child abuse, one count of class-three felony child abuse, and one count of assault.The court was told in the days that followed the attack, Ms Singler “fled” the US and was arrested 11 days later in London.Ms Singler’s hearing, before District Judge John Zani, is expected to last three days. The final decision on whether Ms Singler should be extradited to the US will be made by the UK home secretary.On Wednesday, prosecutor Joel Smith KC told the court Ms Singler’s alleged crimes were “committed against the backdrop of acrimonious court proceedings” concerning the custody of her children with her ex-husband Kevin Wentz.Mr Smith said she shot and stabbed the first two children and attacked the third with a knife, causing “serious lacerations”.”She initially blamed an unknown male, and cast suspicion on her former partner.”The court heard that on 19 December the Colorado Springs Police Department responded to a 911 call reporting a burglary at a Colorado residence at 00:29 local time (06:29 GMT).When officers arrived at the defendant’s address, they found two dead children and a third with a serious injury to her neck. She was taken to hospital.Live rounds and spent cartridges were found in a closet and a “blood-stained handgun” was discovered on the floor of the bedroom, the prosecutor added.A blood-stained knife was also found in the living room of the property, Mr Smith added.The court heard that DNA tests were carried out on the knife and the gun and revealed the presence of mixed profiles matching the children and Ms Singler.Mr Smith added: “Two empty bottles of sleeping tablets were also found and there were no signs of a break-in.”The court heard the third child required emergency surgery, but survived.Mr Smith said Ms Singler blamed her husband for the attack, but it was found he had been driving a “GPS-tracked truck” in Denver, giving what the prosecutor described as a “complete and verifiable alibi”.In the days that followed, the third child, who was not named in court, was moved into foster care after her emergency surgery.On Christmas Day, she told her foster carer that Ms Singler had been responsible for the attack and had asked her to lie to police, Mr Smith said.The prosecutor said the girl was interviewed by police on 26 December, during which time she recounted how the attack had unfolded after the defendant guided all three children into their bedroom.”The defendant told her that God was telling her to do it, and that the children’s father would take them away,” Mr Smith said.The police investigation then led to a warrant being issued by Fourth Judicial District Court in El Paso County, Colorado, for Ms Singler’s arrest.Mr Smith said Ms Singler was arrested in the Chelsea area of west London on 30 December.Ms Singler’s defence barrister Edward Fitzgerald told the court she “denies she is responsible for the death of her two young children and the attempted murder of her third child”.”She is innocent,” he said.Members of Ms Singler’s family joined via a video link, as did the Colorado State prosecutor and officials from the US Department of Justice (DoJ).The extradition hearing continues.