Jon Jordan, News 9

PHOENIX, Arizona -- Authorities are investigating a bizarre car accident out of Arizona involving an Pryor woman.

Investigators first believed 41-year-old Tina Ferlet died when her son, who was driving erratically at the time, slammed into a pickup truck. However after further investigation, investigators determined her 16-year-old son Nathan Ferlet killed his mother by choking her.

According to police, the mother and grandmother picked up the teenager in California and were driving him back to Oklahoma to get him help for mental problems.

"When you say strange, this is perhaps an understatement in this case. As we began to put all this together suddenly the investigation switched from a fatal accident to in fact a homicide investigation," said Phoenix Police Sgt. Tommy Thompson.

Everyone else involved in the accident was taken to the hospital and are all expected to be OK.

Once Ferlet is released authorities said they will charge him with killing his mother.