The man behind the wheel of the pickup truck has been identified as 54-year-old Charles Glaze, according to sources.
Sources say Glaze reportedly crossed from the westbound lanes of Highway 99, over the median and into oncoming traffic, striking four vehicles.
When speaking to authorities, Glaze reportedly said he didn't know what happened before the crash.
The crash left twisted metal and shattered glass across all lanes of the Grand Parkway. Both sides of Highway 99 were closed until late Wednesday night, but have since reopened.
The Harris County Sheriff's Office said five people, including Glaze, were taken to the hospital with non-life threatening injuries.
The crash took two lives, Michael Brown and Linda Fuggiti.
Brown, 73, was known as a true pillar in his community. He was retired and kept an eye on the neighborhood.
"This neighborhood has experienced a great loss with his passing," said Troy Butler, Brown's friend.
Brown, his wife Charlotte, and Michael's sister were inside of his HHR during the crash.
Investigators say Glaze crossed over the median, into oncoming traffic and caused a five-vehicle crash.
Michael died. His wife and sister were rushed to the hospital.
"Charlotte was in the back seat and suffered a broken collarbone," said Butler.
Fuggiti's sister-in-law says Linda was outstanding in every respect. She was in administration for a medical supply company and planned to retire soon.
Her loss and the loss of Michael are felt across the community.
"As the years went on it became more of a family relationship, than just a 'Howdy, neighbor' in passing," said Butler, discussing Brown.
Now Brown's neighborhood is missing a friend and brother who is still watching over them.
"He's not just watching over our little community now but he's watching over all of us," said Butler.
"The best way I can describe it, mass chaos. A huge field of debris, unfortunately," said Katy Police Officer Johnny Alvarez. "The vehicle was overturned. I got on my knees and I entered the vehicle through the rear passenger window. We were applying first aid and we just assisted him in any way we could."
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Deputies said Glaze did not appear to be intoxicated and said he is cooperating with their investigation. Glaze has not been charged in the deadly crash.
The driver apparently has a history of seizures, according to the sheriff's office. It was not immediately known if Glaze was cleared by a doctor to drive.
According to sources, Glaze was reportedly wearing an ankle monitor at the time of the crash on Highway 99.
But new details revealed a twist about Glaze. According to sources, not only does Glaze have a medical history but he also has a criminal history, as he was charged in 2017 with aggravated kidnapping and assault out of Montgomery County.
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Investigators say in 2017 a woman was visiting her son's gravesite when Glaze attacked her at the Klein Memorial Cemetery in Tomball.
Deputies say he assaulted her with a Taser and showed her a gun before tying her up with zip ties and a necktie. Deputies say she managed to escape.
In another incident, deputies with the Montgomery County Sheriff's Office say a man matching Glaze's description reportedly made another woman feel uncomfortable at a different Klein cemetery and she reported that to authorities.
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