Teenager bought a firework which was stuffed through a letterbox and killed ... trends now A teenager told his girlfriend 'people are going to get terrorised tonight' as he bought a firework which was later stuffed through the letterbox of a property, killing a grandmother inside. Kai Cooper is on trial over the death of Josephine Smith, 88, who is believed to have been asleep in bed when the firework was stuffed through the letterbox of her home in Romford, east London, which set the property ablaze on October 28. 2021. Cooper, from Leatherhead, Surrey, denies arson being reckless as to whether life is endangered and manslaughter. Heidi Stonecliffe KC told a jury at the Old Bailey that Cooper, 19, was accompanied to a firework shop by a younger boy who was 15-years-old at the time. He is now aged 17, and cannot be identified for legal reasons. Cooper is alleged to have said to the shopkeeper Mark Vardy that he wanted 'something that is going to go far and quick'. Josephine Smith, 88, who is believed to have been asleep in bed when the firework was stuffed through the letterbox of her home in Romford, east London, which set the property ablaze on October 28. 2021 CCTV footage from inside the shop records Cooper telling Mr Vardy: 'I'm going to throw it in their face bro', and asking which fireworks were the 'best ones to let off at people, not gonna do damage, but shoot off and go bang.' It is alleged that he then told his girlfriend outside: 'Hey babes, come here. I'm trying to get fireworks, let them off at people. People are going to get terrorised tonight.' He then purchased the fireworks, as well as two lighters from a Co-op shop. He and his friend then walked towards Mrs Smith's house in Queens Park Road, where she lived alone. The court heard that Mrs Smith, a Blitz survivor and grandmother of seven, was 'entirely unknown' to the pair. Before they reached the property, the pair set off some fireworks in the street, next to a restaurant and a pub, near cars and towards pedestrians. Cooper has admitted affray by setting the fireworks off in the street. 'It is the Crown's contention that they acted as a team as they did this, with Kai handing (the 17-year-old) the fireworks before they were lit and Kai encouraging (the 17-year-old) to do this,' Ms Stonecliffe told the court. 'It was, it is suggested, the precursor for the altogether more tragic events that occurred shortly afterwards.' Cooper, aged 19, is on trial over the death of Josephine Smith, 88, at the Old Bailey in London (pictured) Cooper's friend took a Megaburst firework and ran across the road towards Mrs Smith's house. He then lit the firework and put it through the letterbox, the jury heard. 'Two explosions occurred in swift succession, just like others that (the defendants) had set off in the street,' Ms Stonecliffe said. 'They caused a fire to start, which burned through Mrs Smith's house. 'By the time the fire service had arrived, the property had filled with smoke and Mrs Smith was found, already sadly deceased, in the upstairs bedroom of the house. 'Efforts made to revive her were unsuccessful and she was pronounced dead at 11.09pm.' Cooper and his friend had already left the scene. According to a statement made by Cooper's girlfriend, Lauren Delossantos, Cooper had been laughing as his younger friend rang across the street to Mrs Smith's home and that he had 'dared' his younger friend to post the firework. She was heard shouting 'no' on CCTV footage as the fireworks were lit. She was arrested but released without further action. 'It was her view that (the 17-year-old) would not have put the firework through the door if Kai had not suggested it,' Ms Stonecliffe said. As many as 40 firefighters rushed to the scene just after 10pm after calls of a two-storey mid-terraced house on fire on October 28, 202 A firework was recovered from the scene, and a post-mortem gave the cause of Mrs Smith's death as smoke inhalation The prosecutor told the court there is no dispute that Cooper and the other youth bought fireworks and lighters that evening, all paid for by Cooper, or that one of them put a firework through Mrs Smith's door. Ms Stonecliffe said the jury must consider whether Cooper was party to the offences by encouraging and assisting the younger defendant. 'It is not in dispute that they were together,' she said. 'Nor is it disputed that they bought fireworks and set them alight, and that they were paid for by Kai due to his senior age. 'It is not in dispute they fired them at cars and people. It is not in dispute that a firework was posted through Mrs Smith's letterbox. 'The single issue in dispute is whether Kai Cooper was a party to those offences, whether he encouraged or assisted [the 17-year-old]. 'It was Kai who was in control during the time that they bought the fireworks, Kai who spoke candidly and luridly to Mark Vardy about his intention that evening, Kai who paid for the fireworks and Kai who carried the fireworks thereafter.' The victim had lived in the Harold Wood area her entire life. Relatives said the mother-of-five and grandmother-of-seven, who separated from her husband 20 years ago, would walk the children to and from school every day. She often used to recall her memories of the Second World War, and how she had to run for cover from Doodlebug flying bombs. Her family added: 'She was a fantastic, loving mum and gran. She was passionate about snooker and darts and was obsessed with Elvis Presley, visiting Graceland a few years ago.' The trial continues. All rights reserved for this news site (dailymail) and under his responsibility