DAYTON, Ohio (WABC) -- New video has been released of the gunman who opened fire in Dayton, Ohio, killing nine people and wounding 17 in a matter of seconds.
Before he opened fire in a crowded bar with an assault weapon Aug. 4, authorities said Connor Betts went drinking.
"We don't see anyone assisting him in committing this horrendous crime," said Dayton Police Chief Richard Biehl.
Police in Dayton revealed for the first time a minute by minute account of the shooter's last few hours that Saturday night, when he went to the Oregon District with his sister and a friend around 11 p.m. without his weapons.
He joined them in a bar, then after about an hour he left on his own and went to another called Ned Peppers. He stayed there for half an hour before leaving and heading to his car, walking right past a police car.
"He's aware of where they were. Or you think he would have to see them," said Dayton Police Lt. Paul Saunders.
Minutes later, he was back, this time wearing body armor and a backpack laden down with his rifle and ammo, and that's when police say he mowed down more than two dozen people before police took him down.
Among the dead was his own 22-year-old sister Megan and even now, investigators can't say if he wanted to kill her, or if she was just a random victim of indiscriminate slaughter.
"We're divided about how whether that was intentional or not. I think it is inconclusive," said Biehl. "But based on the evidence from that night I don't think we can make the call."
Text messages show the 24-year-old gunman knew his sister and their friend were going to a taco stand minutes before he came down an alley and started shooting, Beihl said.
"There's a real question whether he could see who was on the other side," the police chief said, adding that its possible investigators may never come up with an answer.
Authorities have interviewed witnesses, studied video and reviewed Betts' phone while trying to come up with a motive and other factors that led to the mass shooting. So far, there is no evidence he had any help the night of the shooting, Biehl said.
While they don't know why Betts chose his location or what his motive was, investigators do know a lot about his mindset, including his obsession with and desire to commit a mass shooting, the police chief said.
Betts was very familiar with the area and its night spots and had been there the night before, the police chief said. It's clear he had a plan for the mass shooting, although why he chose that place at that time is still being investigated, the police chief said.
In all, he killed nine people and wounded at least 17 others in just over half a minute before officers who were patrolling the area fatally shot Betts, police said. Previously, police and hospital officials said at least 14 people suffered gunshots.
The coroner's report will determine whether anyone besides the shooter was hit by police, Biehl said.
Authorities said that a friend, Ethan Kollie, bought armor and a 100-round magazine for Betts, authorities said. But there was no evidence he knew what Betts planned, they said.
The governor's office said Wednesday that its attorneys weren't aware of any law that "would have necessarily prohibited" the magazine.
Kollie will appear Wednesday in federal court. His attorney said he has been cooperating with investigators.
"He was as shocked and surprised as everyone else that Mr. Betts committed the massacre," attorney Nick Gounaris said Monday.
Prosecutors accused Kollie of lying about not using marijuana on federal firearms forms in the purchase of a pistol that wasn't used in the shooting.
Police have said there was nothing in Betts' background to prevent him from buying the gun.
The weapon was purchased online from a dealer in Texas and shipped to another firearms dealer in the Dayton area, police said.
Ohio Republican Gov. Mike DeWine has proposed a package of gun control measures , including requiring background checks for nearly all gun sales in Ohio and allowing courts to restrict firearms access for people perceived as threats.
(The Associated Press contributed to this report.)
* Follow us on YouTube
* More local news
* Send us a news tip
* Download the abc7NY app for breaking news alerts
Authorities piecing together what led to mass shooting in Dayton
More TOP STORIES News