Elderly couple who died in caravan alongside their daughter and dog from suspected carbon monoxide poisoning Woman in her 40s and elderly parents all die in static caravan Firefighters break into home after call from worried carer Elderly parents named locally as Alfred and Audrey Cook Their daughter Maureen, 46, also named locally as having died Investigation into tragedy near Camborne, Cornwall underway By Lucy Crossley and Steve Nolan A woman and her elderly parents have died from suspected carbon monoxide poisoning at a caravan park. It is believed John Cook, 90, his wife Audrey, 86, their daughter Maureen, 46, and their dog were overcome by fumes from a faulty heater. A helper raised the alarm on Saturday afternoon when she called at the static caravan at Tremarle Home Park in North Roskear, Cornwall. Tragic: It is believed John Cook and his wife Audrey may have been overcome by fumes from a faulty heater Tragic: The static home where John and Audrey Cook and their daughter Maureen died of suspected carbon monoxide poisoning Tributes: A resident leaves flowers outside of the home where John and Audrey Cook died along with their daughter Maureen No one answered the door and a person could be seen slumped in a chair. When rescue workers broke down the door of the caravan near Camborne, Cornwall, after failing to get any kind of response from the occupants, they found the three bodies, and that of the family dog. The alarm was raised at around 1pm this afternoon at Tremarle Home Park, North Roskear, Devon and Cornwall police said. It is understood the family may have been using a heater to keep warm as the region experienced freezing conditions into the weekend Friends and neighbours have today been paying tribute to Mr Cook, 90, who was known to his friends as John, Audrey Cook, 86, and their daughter Maureen, 46. The family's Jack Russell, called Jannie, also died. One neighbour, Sonya Owen, 53, said: 'It's very distressing. I knew the daughter, she was living her with her mum and dad. Everybody is really upset. Margaret Holmes, 65, who lived near the couple and their daughter, said: 'They had lived here for around 40 years and they kept themselves to themselves. Touching: Neighbours have left floral tributes for the family at the caravan park today 'I just can't believe this has happened, it is so sad and I am so shocked, I think we all are, you just don't expect this sort of thing to happen on your doorstep. Everyone will miss them, we used to chat a lot when we were both in the garden. 'I would just like to send my condolences to their family, I can't imagine what they're going through.' Nic Clark, 52, who was good friends with daughter Maureen, added: 'They were a lovely kind family, a great trio. Maureen used to go out and walk her dog, a little Jack Russell, it is so sad what has happened, I understand the dog went with them. They will be sorely missed and I think everyone is just in shock at the moment, I would like to send my condolences to the Cook family. Linda Barr, 84, who lived opposite the family said: 'We have known them for 13 years, it is such a shame what has happened, I really can't believe it. They were very nice people and it is so sad what has happened. 'We're all going to miss seeing them terribly, they've been here for so long it will be strange not having them around.' Friend Judith Clarke said: 'They were a nice family who kept themselves to themselves. Maureen was a gentle soul who looked after her mum and dad. She loved her dog and she always used to fuss my dog Poppy as she walked by. I am absolutely gutted and it's hard to believe they are gone. Julie Boon, 55, said the whole community was left shocked and devastated. She knew the family for 20 years. She said: 'I saw Maureen and her mum on Thursday morning when they were walking their dog. Maureen asked about my dog Rusko and her mum commented on the cold weather and then they went. They were so friendly and this has rocked our lovely neighbourhood to its core. Sue Isaacs, neighbour 'That's the last time I saw them. They were a lovely family who loved their dog and their home. The whole community is shocked and devastated. Jean Carr, 72, said: 'John and Audrey were quite ill I believe, they really didn't get the chance to leave the home very often. I think it was just down to old age, they were very old and have been here such a long time. Maureen loved her little dog, I would see her walking it every day, it really did give her a lot of joy. 'We aren't really a tight knit community, but still, I think this news has shocked everyone and it is just so sad, I really can't believe it.' Sue Isaacs, 58, added: 'My son told me it was on the news and it felt like someone had kicked me in the stomach when I found out what happened, it was horrible. 'I can't sleep knowing what has happened right on my doorstep, it is just awful. Inspector David Eldridge of Devon and Cornwall Police said: 'Shortly before 1pm this afternoon, we were called to a caravan park near Camborne in Cornwall, where a helper had been unable to get a reply from an elderly couple who lived in the caravan. We were able to see that there was a figure sat in a chair but they were unresponsive to knocks at the door. Cornwall Fire and Rescue were called. They forced entry into the property and found that the three occupants were all dead. Emergency: Firecrews rushed to the Tremarle Home Park in North Roskear, near Cambourne, Cornwall and broke down the door of the static caravan An investigation into what caused the deaths is under way, but the incident is not being treated as suspicious. Post-mortem examinations will be held to confirm the cause of death. A Cornwall Fire and Rescue Service spokesman said that a crew from Camborne Community Fire Station attended the scene with a hazardous materials advisor after being called at 12.56pm. The Health and Safety Executive said it would not be investigating as the incident took place at a domestic address. Neighbour Linda Barr Stephanie Trotter, president and director of the independent charity CO-Gas Safety, said Carbon Monoxide was an incredibly lethal gas. 'Less than two percent of carbon monoxide can kill in between one and three minutes,' she said. It cannot be sensed using human senses of smell, touch, sight or hearing. The Department of Health estimates that about 40-50 people die of carbon monoxide and about 4,000 attend A&E every year in England & Wales alone. But the numbers could be much higher because there is no automatic test of carbon monoxide on dead bodies, even in cases of unexplained death. Also, GPs find carbon monoxide very difficult to diagnose because the symptoms are so similar to many viruses. 'It is also difficult because the gas emergency service doesn't carry or use equipment to test appliances for CO and a registered gas installer will tend to change the appliance to make sure it's safe before testing. Grim discovery: Police have said that they could see a figure sat in a chair through the window of the home but could get no response It means that often people who have been poisoned, never know. She added the charity was lobbying MPs to bring about changes to the Energy Bill currently going through Parliament - for more public awareness campaigns and for the gas emergency service to carry and use equipment to test gas appliances for carbon monoxide. Mrs Trotter said: 'We are very sorry to read of these tragic deaths. We send sympathy to family and friends and offer free, confidential help and advice. Camborne Town Council member David Biggs described the incident as an 'appalling tragedy'. He said: 'Tremarle Park is a residential caravan site and has provided homes for people for many years. 'It's a well established facility and is very well run. It was a shock to learn that three people have died there.