Police suspect a Southwest Side woman lured a young expectant mother to her home before the pregnant woman was slain and the child was cut out of her body.

Authorities said a body found in a garbage can early Wednesday in the woman’s backyard in the 4100 block of West 77th Place is that of the pregnant woman — Marlen Ochoa-Lopez, who was reported missing three weeks ago. They said the woman was strangled to death and ruled the death a homicide.

Sources said charges are expected to be filed against a 46-year-old woman, whom family friends say Ochoa-Lopez met on a Facebook group.

The suspect got the 19-year-old woman to come to her home in the Scottsdale neighborhood by offering extra baby clothes for her unborn son, her family says.

Hours after Ochoa-Lopez was last seen April 23, the older woman called 911 for help, saying she had given birth to the boy inside the home on 77th Place.

The suspect told emergency workers she was suffering from “post-delivery issues,” a police source told the Chicago Sun-Times. But DNA tests have shown the child belonged to Ochoa-Lopez and her husband, the source said.

The baby is in the hospital in “grave condition,” the source said.

Anthony Guglielmi, chief spokesman for the Chicago Police Department, would not comment on details of the case except to say that four “persons of interest” were in custody in both the death of Ochoa-Lopez and the “incident involving the baby.”

Police have not identified the people of interest. They previously said Ochoa-Lopez’s car was found earlier this month about a block away from the home of the woman who claimed to have given birth to the child.

Before she went missing, Ochoa-Lopez apparently went to the woman’s home after the two connected on a Facebook group geared toward young mothers. The woman was offering Ochoa-Lopez free baby clothes, according to Sara Walker, a student pastor at Lincoln United Methodist Church who has been helping the missing woman’s family communicate with police.

No one had seen Ochoa-Lopez since that meet up April 23, Walker said — the same day police say the 46-year-old called for help claiming she’d given birth shortly after 6 p.m. at the home on 77th Place.

Ochoa-Lopez was last seen leaving school around 3 p.m. at Latino Youth High School near Cullerton and California — about 8 miles from the home on 77th Place.

The 46-year-old woman later set up a GoFundMe online campaign to raise $9,000 for her baby’s funeral, claiming the boy was sick and about to die, Walker said. An anonymous tip eventually led detectives to check the parentage of the baby with saliva from the missing woman’s husband, Yiovanni Lopez, and hair samples from Ochoa-Lopez’s home, she said.

The grief-stricken husband was at the Cook County medical examiner’s office Wednesday evening. “I have a lot of pain, a lot of anguish, a lot of sadness,” Lopez told reporters in Spanish. “It’s painful to lose your wife, the woman you love the most. It’s painful.”

Lopez said the perpetrators “don’t know the pain they’ve caused” his family.

“We’re gonna have justice with those responsible,” he told reporters. “We’re gonna go hard after them. We won’t let it go.”

Walker said distraught family members had been focused on finding Ochoa-Lopez, who lived in West Englewood, nearly 5 miles away from the home in the Scottsdale neighborhood where the 46-year-old reported giving birth.

A woman who lives near the Scottsdale home, who asked not to be named, recalled seeing an ambulance drive by on April 23. She said she noticed her neighbor standing by her front door cradling a baby that was wrapped in a white towel or sheet.

“I said ‘What’s up?’ and she said, ‘I just had the baby. It’s not breathing,’” she recounted, noting that neither she nor first responders went inside the house.

“She said, ‘I stood up and the baby came out,’” said the neighbor, who recalled seeing blood stains on the woman’s hands and some on a T-shirt she was wearing, but not on the shorts she had on.

“Before she left in an ambulance, she told me several times, ‘Please call up someone to come and lock the house,’” said the neighbor, adding that the woman lived in her parents’ basement.

The neighbor who didn’t want to be identified also said she saw police take the woman into custody on Tuesday along with her daughter and both of their boyfriends. Each was put into a separate police vehicle, she said.

A man who lives down the block recalled seeing the car that was eventually traced back to Ochoa-Lopez. He said it had been parked in the same place for at least a week — about a block from the home where a body was found — and that there was a parking ticket on it.

Julie Contreras, another student pastor at Lincoln United Methodist Church, said Ochoa-Lopez’s “distraught” family was “searching for answers with Marlen. Now they have that answer.”

”It’s a nightmare. It’s as if this family lived through a horror film,” Contreras said. “The family wants [the suspect] prosecuted to the fullest extent of the law.”

Contreras said the family would soon began making funeral arrangements for Ochoa-Lopez.

Meanwhile, Yiovanni Lopez visited his newborn boy Tuesday night at Christ Hospital and named him.

A “tough decision” was ahead in regards to the newborn, who has severe brain damage and would possibly be pulled from life-support in the coming days.

”It does not look good for the baby, but they are praying and hopeful,” Walker said.

Echoes of 1995 case

More than two decades ago, a similar case in DuPage County drew national headlines.

Debra Evans and her two children were killed in their Addison apartment in 1995. Her 7-year-old son Joshua was abducted and stabbed to death. His body was left in an alley.

Ms. Evans’ womb was slashed and her nearly full-term son was removed. The baby, Elijah, survived, and his brother Jordan was unharmed.

Levern Ward, who fathered Elijah and Jordan, is serving a life sentence for murder. So are Fedell Caffey and Jacqueline Williams. Prosecutors said Williams — a cousin of Ward — wanted the unborn child.

Contributing: Luke Wilusz, Nader Issa