A man killed six people, including his wife and two young children, in a brutal knife attack because he could not face the break-up of his marriage, a court has heard.
Damian Rzeszowski is accused of murdering his wife Izabela Rzeszowska, 30, along with their daughter Kinga, five, and two-year-old son Kacper, in St Helier, Jersey, on 14 August last year.
The 31-year-old Polish national is also accused of murdering his wife's father Marek Garstka, 56, her friend Marta De La Haye, 34, and Mrs De La Haye's five-year-old daughter Julia.
Rzeszowski pleaded guilty to manslaughter through diminished responsibility in April, but the pleas were not accepted by the Crown, which argues that the defendant was not suffering an "abnormality of the mind" when the attacks took place.
Kinga and Kacper Rzeszowski
The Royal Court in St Helier heard that Rzeszowski's rampage took place against a backdrop of increasing marital difficulties between himself and his wife.
Solicitor General Howard Sharp, for the prosecution, told the presiding judge Sir Michael Birt and two jurats - similar to magistrates in mainland UK - who are judging the case: "Until around June 2011 the defendant's day-to-day behaviour was unremarkable, but things changed in June and July.
"What was the cause of that change? The answer is to be found in the state of the defendant's marriage. It had been in difficulties before the incident happened, but by this time it was under great strain."
Mr Sharp explained that during this period Mrs Rzeszowska admitted to her husband that she had been having a two-month affair with another man and she threatened to commit suicide.
After learning of his wife's infidelity, Rzeszowski started going out drinking and had a one-night stand, before taking an overdose of pills on 19 July.
In an attempt to save their marriage, the couple decided to travel to Poland to visit their families.
"However, the problems remained and the defendant visited a prostitute while he was in Poland," Mr Sharp said.
The knife attack took place in the couple's St Helier home on the day they returned from their holiday.
Mr Sharp added that Rzeszowski "could not face the prospect of a failed marriage".
Mrs De La Haye and her daughter
Rzeszowski, who has been remanded in Broadmoor Hospital in Berkshire since his arrest, listened with his head bowed and eyes closed as he heard Mr Sharp describe the killings.
Mr Sharp told the court that after the family returned from their holiday in Poland on the morning of 14 August, Mrs Rzeszowska and her father left the flat to go and fetch Mrs De La Haye and her daughter so they could have a barbecue together.
When they returned, they found that Rzeszowski had gone out and left the children by themselves, although Mr Sharp said the defendant could not recall why he left or how long he was away for.
"When he got back, Marta and her daughter had arrived," Mr Sharp said. "His wife remonstrated with him about leaving two young children on their own, and from this point on he says he had an apparent black-out."
Mr Sharp said the argument "probably" happened at 1pm or shortly thereafter and the killings started at around 2.45pm. "We know for sure that 999 calls made at 2.58pm and 3pm when several residents saw the defendant on the street with a knife, which happened at the very end (of the attack)," he said.
This lapse in time, Mr Sharp said, showed that the attacks had not been the product of a momentary loss of control. "It's one thing for the defendant to say he lost his temper in the heat of the moment, it is quite another to say he had an hour and three-quarters to think about it," he added.
Reconstructing the devastating sequence of events which had unfolded inside the flat, the Solicitor General said it was the prosecution's belief that Mr Garstka was the first to be attacked. He was reportedly stabbed nine times while watching television.
Rzeszowski also stabbed his two children and his daughter's friend multiple times during the course of the attack.
Mr Sharp said Rzeszowski attacked his wife in the flat's lounge or hallway, but she was able to move and run through the flat and out into a courtyard.
She then climbed in through the bathroom window and made a "desperate attempt" to call the police using her father's mobile phone. "The number she dialled was 997, which is the Polish emergency services' number," Mr Sharp said.
Her friend, Mrs De La Haye, was able to exit the flat and collapsed after being stabbed outside by some scaffolding. The prosecution could not say exactly where she was attacked, although her DNA was found on the front door.
Mrs Rzeszowska also made it out into the street but was chased by her husband and stabbed again in full view of local residents.
Neighbours tried to intervene but Rzeszowski started stabbing himself as he went back inside the flat. He slumped to the ground with a collapsed lung near where he had attacked his father-in-law.
The trial continues.