California authorities investigating a child abuse case were taken aback when they arrived at the home associated with the alleged incident and uncovered more than a dozen other children.

Officers from the Arcadia Police Department were called to a local hospital on May 7 after a 2-month-old infant was admitted with a traumatic brain injury and intracranial bleeding, according to a press release obtained by Law&Crime. Authorities then proceeded to visit the residence of the parents, 65-year-old Guojun Xuan and 38-year-old Silvia Zhang, located on the 600 block of West Camino Real Avenue. Arcadia is situated in northeast Los Angeles County, adjacent to the Angeles National Forest.

Cops found 15 children in the home, along with several nannies. The Department of Children and Family Services also responded to the home and placed those kids in foster care. Six other kids living elsewhere but associated with the couple were also placed into foster care, according to police.

Detectives obtained surveillance footage of a nanny, 56-year-old Chunmei Li, allegedly “violently” shaking and striking the infant two days before the parents took her to the hospital. By that time, the baby had suffered an onset of seizures, according to cops. Police say the parents “failed to seek timely medical attention” of the baby and arrested them for felony child endangerment and neglect.

On Tuesday, local CW affiliate KTLA reported that Xuan and Zhang run an agency called Mark Surrogacy that pairs couples wanting a child with a surrogate mother. The surrogates were told that the baby would be going to a couple struggling to have a second baby — but it appears that numerous women were all surrogates to the same couple.

Cops are continuing to investigate. Arcadia Police Lt. Kollin Cieadlo told Law&Crime their investigative focus now is on the child abuse case from May. The child remains at the hospital in stable condition, he said, adding that cops will work with the FBI and child services to determine if any other charges are appropriate.

KTLA reports that most of the kids who were taken into foster care were babies and toddlers, but some also were as old as 13.

Zhang issued a statement to KTLA.

“Any accusations of wrongdoing are misguided and wrong. We look forward to vindicating any such claims at the appropriate time when and if any actions are brought,” she said.

Kallie Fell, executive director of the nonprofit Center for Bioethics & Culture Network, is working with one of the surrogate mothers, according to local NBC affiliate KNBC.

“It was her first time being a surrogate mother,” Fell told the TV station. “The baby that she birthed, she is trying to get custody now. She was told by the intended parents that she was their only surrogate mother, that they had one child.”

But the investigation into whether Xuan and Zhang did anything illegal by having multiple surrogate mothers is likely to be muddled, according to Fell.

“There are no laws against hiring multiple surrogate mothers at a time … but as we can see, this case highlights inherent dangers of commercial surrogacy,” Fell said in an interview with KNBC.

The mother Fell spoke with, Kayla Pena, started a GoFundMe page in hopes of gaining custody of the child she birthed in March.

“This little one deserves stability, love, and a safe home. I am prepared and deeply committed to providing that for her, but the legal process to secure placement is complex and costly,” she wrote.