SANTA ANA, Calif. — Jurors Monday heard from the mother of the 6-year-old boy fatally shot in his car seat while he was on his way to kindergarten on the Costa Mesa (55) Freeway in Orange nearly two years ago, as well as the man who fired the gun.

Marcus Anthony Eriz, 26, is charged with second-degree murder and shooting at a vehicle, both felonies, and faces sentencing enhancements for the discharge of a gun causing death. Co-defendant Wynne Lee, 26, is awaiting trial for being an accessory after the fact.

Eriz is accused of killing 6-year-old Aiden Leos on May 21, 2021, as his mother, Joanna Cloonan, was driving him to kindergarten in Yorba Linda in her Chevrolet Sonic subcompact on the freeway.

Senior Deputy District Attorney Dan Feldman finished his case on Monday, leaving open the question of whether Eriz will testify on his own behalf Wednesday when jurors return to court. On Monday, jurors saw video of Eriz's questioning by California Highway Patrol investigators.

If Eriz does not testify, the attorneys will begin making closing arguments Wednesday morning.

A subdued Cloonan, with a service dog at her side to comfort her, spoke softly as she recounted her nightmarish experience just about 8 a.m. that morning as she was driving on the freeway.

Cloonan testified that Lee, who was driving a Volkswagen Golf Sportwagen, nearly struck her car when she cut her off in traffic.

"It happened very abruptly," Cloonan said. "I had it put my brakes on abruptly."

She added that she "felt afraid," and waited until she had a legal opening in the high-occupancy lane to merge over away from Lee's car.

"I didn't want to be near these people," Cloonan said.

After exiting the diamond lane, Cloonan was parallel to Lee's car when she "made a gesture," referring to the middle-finger insult she extended toward the other driver.

Then, she said, "I heard a very loud noise," which sounded like a "big rock hitting the car."

Aiden exclaimed "ow," and Cloonan "looked behind me" and saw him slump his head, she testified.

"I immediately pulled over to the side of the freeway," Cloonan testified. "I noticed he was dying very quickly."

She held him close to try to stanch the bleeding and dialed 911, she testified.

"I wanted to be able to help (him), but the phone was still connected to the Bluetooth, so I was yelling to the Bluetooth while holding him up, his body against mine," she testified.

After a good Samaritan off-duty officer stopped to assist Cloonan in attempting to aid the boy until paramedics arrived and took over, Cloonan "looked at the back of my car and saw a hole and I asked a man, 'Is that a bullet hole? Is that what happened?'"

California Highway Patrol Officer Kevin Futrell, the lead investigator on the case, explained how a fuzzy photo of a suspect vehicle eventually helped detectives get the make and model for the rare vehicle. Eventually, investigators combed through registration records and took about a week and a half to narrow down a list of possible suspects.

Futrell testified that he received "countless" tips from the public.

"I was receiving tips from the East Coast," Futrell said of the intense interest in finding a suspect. "It was nationwide."

Investigators "knocked on every door" along the freeway as they looked for helpful surveillance video, Futrell said.

As investigators were narrowing in on Lee and Eriz, they received another tip that reinforced their belief the two were involved, Futrell said.

During his interview with Futrell and investigator Jeffrey Moody Eriz seemed emotional as he confessed to killing Aiden.

When asked why he fired the gun, Eriz said, "I have no answer really."

He added, "I don't know what led up to it honestly."

Eriz indicated that he kept his loaded 9mm Glock in his girlfriend's car because he had noticed other drivers during their long commute to work from Costa Mesa to Highland were more "hostile" than usual.

"People are so hostile lately," Eriz said.

Lee cut off Cloonan's car, Eriz said, and then a short time later, "They came by next to us to tell us how they felt ... I just grabbed my gun and shot at them."

Eriz said he had to reach over to the backseat behind Lee to retrieve the weapon before, "I just pointed it ... and popped it off."

Eriz told investigators they could find the gun in his tool box at work.

Lee "was upset with me," Eriz said.

"She asked me, 'Why would I do something like that?'" Eriz said. "I don't have an answer. I was stupid. I didn't think about it. I didn't think of the consequences to anyone."

But after she asked him that question, "I started thinking about it."

When asked if he was angry when he fired the gun, Eriz said, "I don't know ... I don't think I was."

He said he has kept asking himself about his motivation and he can't figure what it could have been.

When asked why he didn't turn himself in, Eriz said he was unaware of what had happened. He said he doesn't follow the news and spends most of his leisure time playing video games and watching online videos.

"I just have my PlayStation and watch YouTube videos," he said.

But one day at work someone pointed out to him that authorities were looking for the same car Eriz and Lee took to work during the manhunt for Aiden's killer, Eriz said.

"So I looked it up," he said. "And I thought, 'Oh my God. What have I done?'"

He went out to his vehicle and "had a panic attack." He couldn't do much work the rest of the day, he said.

When he told Lee she was skeptical Eriz was the one police were looking for.

"She said, 'How do you know it was you?'" Eriz told the investigators. "I said it has to be me."

Eriz said Lee "had even more anxiety than I had" about it.

Eriz, who had seen the "Who Shot Aiden" billboards along the freeway after the shooting, contemplated turning himself in, but, he added, "I didn't know how to go about that exactly."

Eriz said he wasn't sure if he should go in with Lee or not, but, he believed she "didn't do anything."

Eriz acknowledged shaving his beard off, but he added it wasn't to change his appearance to foil detectives. He said it was getting too hot that season to keep the beard.

Eriz said he never tried to dissuade Lee from going to authorities.

"I didn't tell her not to tell anyone," he said.

Eriz said that he would have understood if she went forward to the investigators. After the investigators left the room, Eriz could be heard saying out loud to himself, "I'm sorry, Wynne. I love you so much. I'm sorry."