CHICAGO (CBS) — A “person of interest” was in custody Friday afternoon, after a woman and her 4-year-old son were found dead inside their home in Stone Park overnight.

The landlord of the home in the 1700 block of Mannheim Road said he didn’t see 31-year-old Miriam Cruz Hurtado and her 4-year-old son, Corbin Dallas Barraza, all day on Thursday, but did see the boy’s father leaving in Hurtado’s car early in the morning.

Neighbors said the mother and son had moved in just a few weeks ago. Anthony Gomez said, around 9 p.m. Thursday, he heard screaming at their house, so he ran inside.

“They’re saying ‘The little boy’s dead. The little boy’s dead,’ you know, and so I go inside, and the little boy’s on the bed. His neck was bruised,” he said.

Gomez said he also saw the boy’s mother dead near the bathroom. She was bloodied, with injuries to her head and back. Gomez said he broke down and cried.

“It’s rough. I couldn’t sleep last night, you know?” he said. “I mean, it’s still hitting me now, you know? I probably won’t even go to work, because it’s sad.”

Stone Park Police Chief Christopher Pavini said a person of interest was in custody Friday afternoon. Earlier, police said the deaths appeared to be “an isolated domestic violence incident.”

Gomez said it appeared that was what Hurtado seemed to be trying to avoid when she moved in.

“She was nice lady, you know? She cried at times outside, saying that she wants a better life,” he said. “The little kid was always happy. You know, you’d see him in the back playing on the swing. Good little kid, you know? It’s going to be kind of hard, you know what I mean?”

Investigators cordoned off several spots on and around Mannheim Road overnight, documenting bag after bag of evidence.

The West Suburban Major Crimes Task Force was assisting Stone Park police in the investigation.

Neighbors said Hurtado had two other children, but it was not immediately clear where those children were when she was killed.