Two men were injured and taken to hospital when the Zamperla Junior Miami magic carpet style ride collapsed. Source
Accidents
Theme parks and roller coasters are statistically very, very, very safe. Out of the millions of people who ride the thousands of rides every year, there are only a small handful of incidents. You are statistically more likely to be involved in an accident driving to an amusement park than having one at a park. The rarity of accidents is one reason why the media report them, similar to plane crashes.
Every important element of a ride is inspected on a regular basis and every ride is tested every day without passengers before it opens. A ride might not open, or a safety system might activate, if there is an imperfection. For theme parks to operate, they must obtain insurance and one stipulation is their rides are frequently inspected and signed off by a strict Health & Safety governing body. Every theme park does what they can to prevent accidents because the negative press would be bad for business.
Having said all that, theme park accidents still happen…
Heisse Fahrt, Freizeitpark Klotten, Germany
A 57-year-old woman fell 26 feet (8m) to her death from the moving Gerstlauer Bobsled coaster when she slipped from her seat. It is believed that her lapbar was not securely fastened. Source
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Body Count, Pencester Gardens Funfair, Dover, UK
A 14-year-old boy died after breaking into the funfair with some friends the day before it was scheduled to open. The teenager tried to climb the closed attraction only to lose his footing and fall to his death when he became trapped between ride equipment. Source
Chairlift, Anakeesta Adventure Park, Gatlinburg, Tennessee
A 40-year-old woman jumped from the chairlift and died in an apparent suicide attempt. Source
Thunderation, Silver Dollar City, Branson, Missouri, USA
A male employee died from blunt force trauma while working at the park. It believed that the incident took place while performing maintenance on the Arrow Dynamics mine train coaster. Source
Super Star, Palace Playland, Old Orchard Beach, Maine
A 10-year-old boy suffered a head injury when he fell off the HUSS Troika. Despite the bleeding wound, he was conscious and alert when emergency officials arrived at the scene and was transported to hospital. Source
Cobra, Tivoli Friheden, Aarhus, Denmark
A 14-year-old girl died when the last car of the Sartori Energizer inverted coaster detached from the track and was left hanging under the rest of the train, leaving several people trapped. The park decided to tear down the coaster following the tragic accident. Source
Chair Swing, Madonna delle Grazie Festival, Italy
Twenty people, including a 12-year-old girl, were injured when a chair swing ride at a street fair in Palma Campania became unbalanced as it came off its footing and tipped over. Source (in Italian)
Ballontoren Calidius, Sprookjesbos, Valkenburg, Netherlands
Two adults and one child were hospitalized after their gondola, designed to look like a basket attached to a hot air balloon, fell approximately 30 feet (10 m) to the ground. Source
Crazy Mouse, Foire du Trone, Paris, France
A 40-year-old employee at the giant Parisian funfair died after being hit by a car of the Zamperla wild mouse coaster he was working on. Source