Triple killer Michael Atherton was 'good man' says son The 17-year-old lost his mother, Susan McGoldrick, 47, her sister, Alison Turnbull, 44, and his cousin, Tanya Turnbull, 24, in the tragedy in Horden, Peterlee, County Durham, on New Year's Day when his father blasted them with his shotgun before killing himself. At the end of the day, we have lost four loved family members and we hope they are all at peace now. The statement was released as the Independent Police Complaints Commission (IPCC) launched an independent investigation into "firearms licensing matters." IPCC commissioner Nicholas Long said: "At this tragic time, our thoughts and sympathies are with the families and friends of those who died in Horden on Sunday evening. We have launched an independent investigation and are committed to fully examining the issues around the granting of Mr Atherton's firearms licence and subsequent renewals. I have determined that an independent investigation should be undertaken examining police involvement in the grant of a firearms licence to Mr Atherton. My condolences go out to the families of those who died, their friends and the wider community of Horden. The shotgun murders raised concerns about firearms legislation after it emerged the killer had his guns taken from him by police three years ago following concerns about his mental health. He successfully applied to have his weapons returned after his family raised concerns that he had threatened to shoot himself in 2008. Durham Police confirmed that the weapons were taken from Mr Atherton's house as a precaution, but as he insisted there had been no threat to harm himself, they were returned. That decision followed national procedure, a force spokesman said. "It was one person's word against another," he said. If there was no grounds for applying for the revocation of a firearms licence, the guns would be returned to the firearms licence-holder. Prime Minister David Cameron's official spokesman said the Government had no plans to revisit UK gun laws which were "amongst the toughest in the world." A police cordon remains in place at the scene. Inquests into the four deaths will open at Chester-le-Street Magistrates' Court at 10am tomorrow. Meanwhile, more details emerged about how Mr Atherton's weapons were returned to him after being confiscated. Police were called out to his home on September 10 2008 amid concerns that he said he would harm himself, and his weapons were removed. He applied to get them back and they were returned to him on November 18 that year.