Piecing together these scant clues in search of a motive in this weekend's shootings in Kalamazoo, Michigan, has not produced any answers.

Jason Brian Dalton, 45, is charged with six counts of murder in the nearly five-hour rampage. According to detectives, Dalton told them he "took people's lives."

Police said Tuesday that Dalton did not have a history of mental health issues. And on Wednesday, Kalamazoo Public Safety Chief Jeff Hadley told CNN that Dalton legally bought the 9mm handgun he allegedly used in the shootings, though he did not have a concealed pistol license.

Dalton earned an associate's degree in law enforcement from Kalamazoo Valley Community College in 1992, the school said Wednesday. Records show Dalton enrolled at the college in 1989, said Mike Collins, the college's executive vice president of academic and student services.

Two people who crossed paths with Dalton the day of the deadly shootings shared a few details of those encounters.

The suspect switched cars

Dalton was a driver for Uber and picked up fares between the shootings, a source close to the investigation said.

Matt Mellen was one of Dalton's passengers before the bloodshed started.

JUST WATCHED Kalamazoo Uber rider: 'You're not the shooter are you?' Replay More Videos ... MUST WATCH Kalamazoo Uber rider: 'You're not the shooter are you?' 02:03

About a mile into the trip, Mellen told CNN's "Anderson Cooper 360°," Dalton received a phone call. Mellen heard Dalton tell the caller that he had a rider at the moment and would call back after dropping the passenger off.

Dalton hung up and then started driving erratically, Mellen said.

Dalton ran red lights, squealed the tires and nearly sideswiped another vehicle, Mellen said.

Mellen pleaded for the driver to stop and let him get out, but he initially refused. Once Dalton slammed on the brakes, Mellen jumped out of the car and called police, he said.

"I was actually picked up in a different vehicle than the vehicle he was apprehended in," Mellen said. "I was picked up in a Chevy Equinox -- silver Equinox -- and he was apprehended in a darker-colored HHR."

During the hours-long search for the gunman Saturday night, authorities said they were looking for a silver or dark blue car.

Hadley, the Kalamazoo public safety chief, confirmed that Dalton switched cars. Dalton allegedly committed the first shooting in the Equinox, then went home and started driving the HHR, Hadley told CNN.

Circling a parking lot

Tiana Carruthers was the first victim, authorities said. She survived after being shot in front of her children.

Neighbor Tammy George said Carruthers was looking after some children, including her own, at a playground.

George, who was inside her home when the shooting happened but later talked with witnesses, said that Carruthers had an instinct something was wrong when a car drove up.

The driver reportedly asked for someone named "Missy" or "Misty" before circling the playground in his vehicle.

At that point, George said, Carruthers "just knew something was wrong and told (the children) to run."

Carruthers then was shot.

The neighbor said she believes the shooting was random. Even though the suspect asked for someone by name, George said she thinks it was a ploy to drive around the complex.

About 15 casings were found on the property, George said. Four bullets hit her apartment, including one that penetrated the wall and entered a closet. It was stopped by an insulated cooler stored inside.

Kalamazoo shootings

The gunman then went on to shoot seven more people at two other locations Saturday evening, authorities said.

The suspect killed Richard Smith, 53, and his son Tyler, 17, at a car dealership, police said.

The last shooting happened in the parking lot of a Cracker Barrel restaurant, with Dorothy Brown, 74; Barbara Hawthorne, 68; Mary Lou Nye, 62; and Mary Jo Nye, 60, being killed. A 14-year-old girl who was in the passenger seat of one of the women's vehicles also was struck but survived.

Two hours after the final shooting, police arrested Dalton without incident in downtown Kalamazoo and also seized a weapon from his car.

Heavy-duty jacket purchased at gun store

A surveillance photo shows the suspect in a gun store where he bought a jacket.

A few hours before the rampage started Saturday, Dalton walked into Southwick's, a gun shop in the nearby city of Plainwell, owner Jonathan Southwick said.

Dalton was a regular at the store. He smiled, laughed and hugged an employee, Southwick said.

He spent about 10 minutes in the store before buying a heavy-duty jacket designed to carry a concealed weapon.

The gun store owner said Dalton didn't give him any reason to be alarmed.

'He was polite, meek and mild'

Dalton had no mental health history, the public safety chief told CNN, and was not on any medications.

"Behind the scenes during the arraignment my team said he was polite, meek and mild," Hadley said. "He was completely unaffected by anything."

As authorities tried to gather more clues about Dalton's life, they found 11 rifles at his Kalamazoo home, a law enforcement official told CNN.

The suspect is married with two children. Family members said they are bewildered about what happened.

"This type of violence has no place in our society, and we express our love and support for everyone involved," the Dalton family said in a statement. "We intend to cooperate in every way that we can to help determine why and how this occurred."