A Daytona Beach rollercoaster ride which flipped over and threw riders 34 feet to the ground passed a safety inspection just hours earlier.
The Sandblaster ride is more than 40 years old and has a history of defects but was deemed to be in safe working order he same day the crash happened.
A car overturned sending two riders plunging to the ground with serious injuries.
Eight more people had to be rescued by emergency crews including two who were trapped in the dangling car virtually upside down.
Four of these were taken to hospital.
"The front car which was holding four passengers completely came off the tracks," said Daytona Beach Fire spokeswoman Sasha Staton.
Investigators are still unclear how it derailed, saying the coaster’s track didn’t appear to be damaged.
It was reported that an inspection found cracks in the track and major corrosion to the ride only a month ago.
The ride was taken out of service then but the defects were apparently rectified before the latest safety inspection.
It was also halted in February 2017 due to corrosion and broken handrails.
"First and foremost, we’re concerned about the individuals who were injured last night. Their well-being and recovery is of the utmost importance. Department inspectors conducted a thorough inspection of the ride, and it was found in compliance with state law," the Florida department of agriculture and consumer services said in a statement.
"We have launched an investigation to determine the cause of the accident, and anyone who should be held accountable will be held accountable."
