ALAMEDA (KRON) -- Four of the six teenagers injured in an accident Friday in Alameda are now out of the hospital, police say.

The 15-year old driver of the car still has life threatening injuries at Highland Hospital.  Another victim is at Children's Hospital in Oakland with back injuries.

Police continue to put together the details of how the six teens managed to take a parent's car and slam head-on into a tree. They're also looking into how some of the underaged teens managed to get access to alcohol.

Police say they expect the investigation to continue for quite a while.

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