LITTLETON — A 62-year-Wold Littleton woman was pronounced dead at the scene of a head-on crash Wednesday afternoon.

Nora Jacob-Marai was driving a 2002 Toyota MR2 west on Union Street at the 800 block when the car “veered off the roadway to the right, collided with a guardrail, traveled back onto the roadway,” and crossed the double yellow line, Littleton police said in a news release.

Jacob-Marai’s car then hit a 2001 Chevrolet Avalanche driven by Nancy Gledhill, 44, of Lancaster. Gledhill was treated and released at the scene, according to police, who said there were no other people in either vehicle.

Speed and alcohol did not appear to be contributing factors in the crash, police said. There was speculation at the scene that — considering the erratic path her car traveled — Jacob-Marai may have suffered a medical emergency prior to the accident.

But New Hampshire Deputy Chief Medical Examiner Jennie Duval, who performed an autopsy on Jacob-Marai Thursday morning, said that was impossible to establish with certainty.

“You rarely can reveal evidence on the cause of a crash like this. She died from multiple blunt-impact injuries,” Duval said late Thursday afternoon.

Both vehicles came to rest in the Route 116 roadway, and that highway was shut down for about three-and-a-half hours Wednesday afternoon and evening, police said.

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