A pair of Long Island teens were killed in a grisly crash on the Southern State Parkway early Thursday morning in Islip, police said. 

Troopers responding to a 911 call for a vehicle rollover discovered a mangled 2010 Toyota Prius overturned on the shoulder near exit 43A at around 2:00 a.m., according to authorities. 

Two youths — 18-year-old driver Oliver Charles, of Deer Park, and 17-year-old passenger Dymond Saunders, of West Babylon  — died at the scene, cops said.

Three other passengers in the Prius were rushed by medics to a local hospital with non-life-threatening injuries. 

It’s unclear what led to the crash. 

New York State Police said the cause is under investigation.