"Tell my mom I love her": Teen trapped in van calls 911 before death

CINCINNATI (AP) -- An Ohio county prosecutor has opened an investigation into the circumstances surrounding the death of a teenage boy who became trapped by a minivan bench seat.

WCPO-TV reports Hamilton County Prosecutor Joe Deters said Thursday his office is seeking experts to help investigate 16-year-old Kyle Plush's death Tuesday in the parking lot of Seven Hills School in Cincinnati.

Deters says the teen died of positional asphyxia.

The teen called 911 at 3:16 p.m. Tuesday saying he was in "desperate need of help" and later asked a dispatcher to "tell my mom I love her if I die."

Authorities say officers searched but didn't find the minivan. A relative found the teen and the minivan nearly six hours later.

Cincinnati police and the Hamilton County Sheriff's Office also are investigating.