McKINNEY, TX -- We're learning more about the Anna man who opened fire on a North Texas Police Station. Police say 29-year-old Patrick Gray Sharp was the shooter in Tuesday morning's attack on the McKinney Public Safety building.

Sharp drove up to the building at 9:00 a.m., in an F150 pickup truck, set it on fire, and then began yelling and shooting at the building and officers. Sharp was soon killed, either by police fire or at his own hand. Maddie Garrett takes us step-by-step through what happened, and just who this man was.

"You could just hear gun shot after gun shot," said Matt Paine.

Paine was driving down Taylor Burk around 9 Tuesday morning, when he caught this video on his cell phone.

The truck that Patrick Sharp had set on fire at the Public Safety Building was filled with ammunition that was firing off. The trailer carried woodchips, gasoline, fertilizer, road flares and ammonium nitrate. Sharp was only a few feet away rapidly shooting at Police officers and innocent people.

"It's very scary to think I was 30 to 50 feet away from this man with a gun shooting at just what appeared to be random people, to know that my wife and my son were with me you know that's, that's very scary," Paine said.

Paine wasn't the only person shaken up. As the gunman crossed into a field he headed toward the Collin College Park Campus, opening fire on an unsuspecting campus police officer and the school's records building.

"Students and staff who saw the bullets who saw may have seen the gunman are shaken, we've already offered counseling to them," said Lisa Vasquez with Collin College.

But perhaps the most shaken are McKinney Police Officers, who can't imagine why anyone would plan and carry out an act as terrible as this. They say he appears to have no criminal record, and no history with the police department.

"This doesn't make any sense to any of us, the act is completely senseless that we know of, and we want to know what his motivation is for targeting this city, the public safety building, and members fo the campus," said McKinney Police Chief Doug Kowalski.

Kowalski says they believe Sharp used the truck as a diversion to draw people out of the building so he could open fire on them. He's calling it a suicide by cop.

"He had a plan, he was activating his plan, he was heavily armed he looked like he knew what he wanted to do, what we don't know is why he wanted to do it," Kowalski said.

Kowalski says the chaos only lasted about five minutes. Sharp was soon killed in what's being called his "sniper's nest" on the edge of the woods, just 150 yards from the Public Safety Building. Police still don't know if Sharp died from officer's gunshots--or at his own hand.

"it's unprecedented, there are individuals out there for whatever reason they get bent in the wrong direction and go out and instead of doing what normal citizens would do in society they go out and perpetrate evil," Kowalski said.

Police believe Sharp acted alone, but are still trying to find out if anyone else was involved.