A parents nightmare.
But why is this local tragedy brought to our attention?
They were pretty much children. The OP states that they'd taken the car without permission, the oldest - a licensed driver - was driving.
Bad planning, not to ask permission to take the car, not to let a responsible adult know where they were going, when they expected to get there. 8 teenagers in a car is not good, especially if it's a new driver. SUVs are v. unforgiving cars - they've top-heavy, too sharp a turn & the car goes right over. For teenagers, SUVs are virtual deathtraps - because they amplify driving mistakes, instead of compensating for them by design.
As the rescue squad said, if they'd gotten there in time, the exposure to cold water can help prolong life. 2 of the teens got to hospital in full cardiac arrest, but later died.