Deputies are currently investigating two "very serious" car crashes that occurred within minutes of each other on Sunday night.The Polk County Sheriff's Office said the first crash happened on Alturas Babson Park Cutoff Road near US 27 in Frostproof.Deputies were dispatched around 8:21 p.m., where they found four vehicles and ten people that had been involved. According to an investigation, a 2010 Dodge Ram crossed the center line and collided with a 2019 Ford F-150 pickup and a 2013 Ford Explorer. After the crash, some involved exited their vehicles. PCSO said a 2017 Chevy Silverado traveled onto the scene and collided with the Explorer, causing it to rotate and hit three victims. The Silverado then struck two other victims and dragged them for a short distance.Nine of the ten involved people were injured, with three transported by ambulance and three others taken by helicopter to hospitals.Two of the victims are still hospitalized with life-threatening injuries, as well as a 13-year-old girl with apparent non-life-threatening injuries. The road was closed for around six hours.At 8:36 p.m., deputies were dispatched to a second crash north of Lakeland on Rockridge Road near Country Place Road.PCSO said a 1992 Chevrolet Silverado pickup truck was traveling east on Rockridge Road when it left the road and struck a wooden power pole. When first responders arrived, they found the driver, 22-year-old Jerome Cooke, who had already passed away inside the vehicle.Rockridge Road was closed for around four and a half hours.Deputies are still investigating both crashes. There are no additional details at this time.