The driver of the Fiat Uno that crashed Princess Diana's Mercedes is reportedly not the culprit of her tragic death, an investigator said.

Twenty-five years after Princess Diana died, royal fans are yet to move forward and forget the tragedy of the Princess of Wales yet. As the world mourned to mark her death anniversary, investigator Martine Monteil said that the Fiat Uno's driver should not be blamed for her death.

In the Channel 4 documentary series "Investigating Diana: Death in Paris," Monteil - who now serves as Brigade Criminelle's head - spoke up about Le Van Thanh. The suspected driver of the white Fiat Uno has never been interrogated over the incident.

Still, the investigator reportedly believes that Van Thanh is not the culprit at all.

"I have frustration about the Fiat Uno because I like a well-finished business. For sure, it's out there. Unfortunately, we don't have it," he said.

Per Monteil, the driver of Fiat Uno was only driving quietly when the royal princess's car zoomed at high speed and bumped into the vehicle.

With that, he is convinced that the responsibility should still be with Mercedes.

Who Is Le Van Thanh?

Before the documentary aired, Radar Online spoke with the Fiat Uno driver after he was identified and linked to the crash. The Channel 4 documentary disclosed that Van Thanh has not been tracked down.

He told the news outlet that nothing is free in life, so he asked for €500,000 (approximately $500,300) before he could provide details about the case.

He has been a highly-suspected driver of the car involved in the fatal crash in 1997. Diana's bodyguard Trevor Rees-Jones - who was the only person who survived the incident - also recalled seeing a vehicle similar to the Fiat Uno before the crash and collision.

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Princess Diana died alongside Henri Paul and Dodi Al Fayed: the latter died on the scene. The royal princess was still able to reach the hospital after Dr. Frederic Maillez helped her at the scene.

While she was being transported to Pitie-Salpetriere Hospital, her status immediately and suddenly deteriorated. She eventually suffered a cardiac arrest. The medical staff stopped administering AED and CPR.

Hours after the crash, doctors performed a cardiac massage while the heart surgeons tried reconnecting a ruptured blood vessel near her heart. Unfortunately, she died at 4:00 a.m on that day.

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