OSCEOLA COUNTY, Fla. (WESH)  —It’s been four months since first responders walked up to a 2006 Porsche Cayenne involved in what looked like a single-car fender bender along Florida’s Turnpike in Osceola County.

Latifa Lincoln, 45, and her 3-year-old daughter, Maksmilla Lincoln, were found dead inside. A strong odor forced first responders back. Three of them reported breathing problems. Investigators have since determined the mother and daughter did not die as the result of a crime, but questions remained, how did they die?

After months of intensive investigation on the vehicle at the medical examiner’s office in Orlando, Asst. Medical Examiner Dr. Gary Utz said he suspects mother and daughter died of hydrogen sulfide intoxication, likely as the result of a defect in the car’s battery.

“It’s unprecedented,” Utz said. “I haven’t been able to find another case.”

Utz said he found elevated levels of hydrogen sulfide in the victim’s urine.

He sent the battery to the National Highway Traffic Safety Administration in hopes of having more tests done. He’s also sent “darkened coins” found in the SUV to an Ohio lab in hopes of determining the substance on them is hydrogen sulfide. The clear, flammable gas can smell like rotten eggs. Hydrogen sulfide in high concentrations can cause sudden death.

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Unlike many vehicles which have the battery under the hood, the Porsche Cayenne battery is found under the driver’s seat.

Vehicle identification records confirm Lincoln bought the car in May from an East Orlando dealership.

A manager at Auto Express on Goldenrod Road confirmed they sold the SUV to Lincoln.

“We feel sorry for the lady,” said finance manager Ron Telleysh. “She used to come in here all the time with her little daughter.”

He said the vehicle had never been involved in a crash. The only work they did on the SUV was some upholstery repairs to the back of the vehicle’s passenger seat. WESH 2 confirmed through vehicle identification records there is no crash noted in the vehicle’s history.

In recent weeks, Telleysh said the vehicle was returned to the dealership and repossessed by the insurance company which owned the vehicle. It has since been scrapped, he said.

A spokeswoman for the NHTSA said, “We do not have an open investigation on this.” She said she would check with their vehicle defects division to see if they planned to test the SUV’s battery.

Until he finds out that answer, Utz said he will hold off making his suspicions official as the cause of death in the ongoing mystery.

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