Officers in Pueblo discovered the remains on January 10 when the storage unit was being cleared out due to unpaid rent.
The items in the storage unit included a metal container filled with hardened concrete and the child’s remains were found inside, Sergeant Franklyn Ortega from the Pueblo Police Department said.
Pueblo Police are still searching for two other children in connection with the investigation. The pair were aged 5 and 3 when they were last seen in the summer of 2018 in Pueblo.
Police want to make sure Jesus Dominguez, aged 10, and Yesenia Dominguez, 9, are safe.
Mr Ortega said there has been “no sign, no indication of these children” since their disappearance.
Police have spoken with their parents, Mr Ortega said, but the children had not been reported missing.
It is not immediately clear how the two children are connected to the remains found in the metal container.
The victim’s identity will be released by the Pueblo County Coroner after their next of kin have been informed, police said.
Officers did not release any information about the age of the victim or when the child was believed to have died.
Investigators have interviewed two people of interest, police said. Mr Ortega declined to say whether the parents were the persons of interest in the case.
Pueblo, home to about 110,000 people, sits 45 miles south of Colorado Springs
