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Reports of injuries - and possibly deaths - were expected to start coming in overnight in Queensland as the severe category 4 cyclone that thrashed the state's coast began to slow. The cyclone first hit the Whitsundays, including Hamilton Island where dozens of Kiwis were holidaying. Wellingtonian Emma Gibbons and her family were staying at the Beach Club resort. Gibbons said guests were being told to hunker down in their rooms overnight. If necessary they were to shut themselves in the resort's bathrooms, where there were no glass windows. Witnesses reported winds "like freight trains" thrashing the island and trees being uprooted as the cyclone's destructive core passed over. Gusts up to 263km/h were reported at the island's airport. Witnesses on Hayman Island, the northernmost island in the Whitsundays, spoke of an "eerie silence" as the eye of the storm moved over. Around 30,000 people were told to evacuate along the north coast of Queensland, including more than 20,000 in low-lying Mackay as storm surges pushed high tides up by nearly 1m. Cyclone Debbie made landfall on the mainland around 12.40pm between Airlie Beach and Bowen, bringing chaos and scenes of destruction including windows breaking, buildings shaking and sheets of metal flying down the street. People were warned to stay indoors and not be tempted to go outside even as the eye passed over, bringing clear skies. But despite the warnings, footage emerged of young men boogie boarding on a debris-strewn beach. At least one man was taken to hospital, having been badly injured by a falling wall in Proserpine, inland from Airlie Beach. Another person was killed on Monday in weather conditions related to the cyclone. Prime Minister Malcolm Turnbull told the Australian Parliament the situation was "deteriorating rapidly" and activated the disaster response plan. The Australian Defence Force was mobilising soldiers, vehicles, aircraft and other resources to respond to Debbie, clearing debris and opening roads. The Insurance Council of Queensland declared the cyclone a "catastrophe". Debbie was downgraded to a category 3 as wind speeds fell to 155km/h near the centre, with gusts to 220km/h. Hurricane-strength winds and heavy rain were expected to continue through to this morning. High winds had prevented emergency services from moving in the worst affected areas, and more than 48,000 homes were without power. Queensland police commissioner Ian Stewart said power outages meant many people had no way of contacting emergency services and those people "could be in a difficult, dangerous or tragic situation". He asked people to watch out for looters and send photos to the police if they saw anything suspicious. Once winds calmed affected residents were being urged to stay indoors to allow emergency services to move quickly to get to the people who needed help. Poor light in the evening would likely hamper rescue efforts and many people would be waiting till Wednesday morning as the system weakened and became a tropical low.