Sheriff: Highway sniper's writings show he "idolized" Parkland shooter Nikolas Cruz

GAINESVILLE, Ga. -- A sniper who killed himself after firing on cars and injuring people on a Georgia highway idolized the Parkland, Florida school shooting suspect, a sheriff said Saturday. A sheriff says 26-year-old landscaper Rex Whitmire Harbour fired at least 17 times and hit at least seven vehicles traveling northbound on Georgia 365 outside Atlanta around noon on Friday. 

Two people were wounded and a third was hurt by broken glass. None of their injuries were life-threatening.

Authorities believe Harbour was firing at random and wasn't targeting anyone, reports CBS affiliate WGCL. A search of Harbour's Snellville home, where he lived with his parents, turned up "hate-filled" handwritten documents, officials say.

WSB-TV Atlanta reported that Harbour's mother told investigators her son was mild-mannered and quiet. But the writings suggest he viewed Parkland, Florida school shooter Nikolas Cruz as a "hero" who gave him "courage and confidence," said Hall County Sheriff Gerald Couch.

Couch said the writings indicated Harbour "idolized" Cruz, who killed 17 at Marjory Stoneman Douglas High School in February.

Couch told a news conference that a deputy chased after a suspicious car pulling out of a wooded area adjacent the highway on Friday. He said the suspect shot himself in the head, and his car rolled to a stop. Harbour later died at Grady Memorial Hospital.

Couch said investigators found three 9mm handguns, a 12-gauge shotgun, a BB-gun, and more than 3,400 rounds of ammunition inside his vehicle.  Deputies found 17 shell casings from Harbour's nine millimeter just off of Highway 365, reports CBS affiliate WGCL.

"What his motivation was other than just hate, we don't know at this time," Couch said. State investigators and the FBI turned up no criminal history. "He had the weapons, the ammunition and obviously the will to inflict a lot of harm and a lot of hate."  

Crime scene investigators also found a trail camera in nearby woods, possibly set up by a Hunter, that captured Harbour as he was walking towards the area where he allegedly took a position to open fire at the drivers.

A 72-year-old man was reportedly shot in the hip and a 54-year-old man was shot in the leg. Both men were transported and expected to recover.