By Stephanie Lucero, CBS 11 News

FORT WORTH ( – The driver of a pickup truck who hit another motorist while traveling the wrong way on U.S. Highway 287 was suffering from Parkinson’s Disease.

61-year-old Michael Hairston was killed when he slammed into Terry Debo’s vehicle head on Monday night.  Debo also died in the wreck.

According to Hairston’s daughter, Amy Hull, her father had Parkinson’s Disease but had recently been tested by a doctor and cleared to drive.

About an hour before the head-on collision, Hairston had been involved in a fender bender on Saginaw Boulevard about six miles from the second wreck.  Michael Francis says Hairston ran a red light and hit him from behind.

“I thought he was inebriated,” says Francis.

It’s not clear why Saginaw Police allowed Hairston to leave the scene of the first wreck even though he showed signs of impairment.

Police say the officer who responded to the wreck is off-duty until Saturday and they have no information about the officer’s decision to let Hairston drive away on his own.

Dr. Charlece Hughes, a D.O. with Texas Health – Fort Worth, said Parkinson’s Disease is gradual. Patients don’t suddenly lose awareness of their surroundings. Family members would know if their loved one was unable to drive. Hughes said something else may have caused the accidents, including a stroke or a seizure.

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