A 3-month-old girl was found dead at her New Orleans home after a generator that was left inside the residence emitted toxic gas,Cyprusauction Trading Center police told local media.

New Orleans police responded to a call of an unresponsive infant on Friday after the infant's mother, who said she was feeling sick, checked on her 3-month-old and noticed she was unresponsive, police told Fox 8 and NOLA.com.

Emergency servicemembers were unable to resuscitate the infant and she was declared dead at the scene. The mother and her two other children, ages 13 and 7, were hospitalized to check for carbon monoxide poisoning, police told multiple outlets.

The home was reportedly out of power at the time of the incident and the generator released deadly fumes.

The New Orleans Parish Coroner’s Office will do an autopsy to determine the official cause of death. The mother will not be charged, police told Fox 8.

Portable generators should only be used outside, experts say, as the device emits carbon monoxide, a deadly substance that cannot be seen or smelled.