A California man who killed his ex-wife and fled with his 9-year-old son had battled with her over money and their former home, according to court documents.

Konstantin Morozov, 48, was killed Tuesday night by Los Angeles police, more than 100 miles (160 kilometers) from where his wife was found dead Monday night in Santa Maria. The boy, Daniel Morozov, was unharmed.

Morozov and Natalia Morozova divorced in June. But there were "heated discussions" over a requirement that he pay her $200,000 in return for keeping their home near Santa Maria, according to court documents cited by KSBY-TV on Wednesday.

Morozov missed last month's deadline to pay half the money. He and his former wife had been scheduled to meet at the county clerk recorder's office on Wednesday for Morozov to hand over some of the money.

Court documents also indicated that the two were splitting custody of Daniel.

A statewide Amber Alert was issued after the boy vanished and his mother was killed. It urged people to watch for cars that Morozov might be driving.

Two different cars identified in the alert were found abandoned Tuesday before police from the two cities. FBI agents tracked Morozov to a friend's apartment complex in the San Fernando Valley area of Los Angeles.

Morozov was shot as he left the apartment with his son and went into the street. The father died at a hospital.

Tatiana Moran said she watched from a balcony as the police surrounded the father and son outside of her building.

The youngster was wearing blue pajamas, she told KABC-TV .

"When he finally got on the ground, the little boy just lost it," she said. "He started crying. Then the cop pulled him and said, 'You know you're going to be OK. Everything's fine.' And then they just rushed him to another car."

After that, she heard a commotion outside her view and heard authorities warn Morozov several times before he was shot, Moran said.

The boy is in custody of child-protection officials and will be turned over to relatives when they are found, authorities said.

Morozova had a tumultuous relationship with Morozov and had expressed fears for her safety, said a friend, Irina Malkmus.

"She told me she and her husband had a lot of domestic issues over the years, and she went to the police many times," Malkmus told the Santa Maria Times . "Then she told me that she was going to go through with the divorce, and try to get custody of her son."

"The last few years after she began pursuing divorce became really dark for her," Malkmus said Tuesday evening. "I remember she told me that she was scared, she was afraid and she even ran to the woman's shelter a few times to hide in the past."

Morozova's relatives were in Russia so her son "was the one thing she had left in her life" in the United States, Malkmus said.

Morozov was described as a Ukrainian immigrant and a skilled at-home nurse.

"I told my girlfriend, hey, that's the guy who took care of me, he's an excellent guy, he did an excellent job on my foot," Javier Romero told KEYT-TV . "He probably should have gone to counseling with the wife. I'm just in shock. Sad. This shouldn't have happened."