Police in Oregon say an apparently suicidal woman was being treated for critical injuries after she intentionally set herself on fire, crashed her car into a guardrail, and jumped 40 feet off a bridge Thursday.

According to The Eugene Register-Guard, the 39-year-old woman had recently been reported missing by her family. The paper reported that a 911 caller first spotted the woman's car at around 12:30 p.m. local time. The caller told emergency responders that the interior of the woman's car appeared to be on fire, and she was driving recklessly.

After the car crashed into a bridge guardrail, witnesses told police the woman jumped out — on fire — and began taking her clothes off as she ran to the edge of the span.

Truck drivers tried to put out the flames with fire extinguishers and another person tried to grab the woman, but she was still able to jump, police said.

"I am thankful for the witness who helped us piece together what happened and was trying to keep this woman from jumping off a bridge," traffic Lt. Doug Mozan said. "Her efforts were nothing less than heroic."

When the car crashed, a piece of its bumper sailed over the bridge, injuring a 40-year-old woman below. The pedestrian was treated for minor injuries, police said.

The car was still engulfed in flames when police arrived, Mozan said. He added that police believe the woman used an accelerant to fan the flames, but did not elaborate. 

The accident damaged the bridge and traffic was backed up for almost two hours. The fire and crash remain under investigation. It is not clear if any charges will be filed. 

The Associated Press contributed to this report.

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