A van carrying about 10 people flipped while traveling on Florida's Turnpike near Yeehaw Junction.
Emergency rescue teams from Indian River and St. Lucie counties responded to the accident, which happened at about 7:30 p.m. at mile post 175.
Four passengers were taken to Indian River Medical Center and the rest were transported to Lawnwood Regional Medical Center & Heart Institute, said Brian Burkeen, spokesman for Indian River County Fire Rescue.
One passenger suffered serious enough injuries to need emergency treatment at Lawnwood's trauma center, said Burkeen, who didn't know the exact number of victims.
Officials are looking into the cause of the rollover, he said.