Child abuse investigators are awaiting autopsy results on a 3-year-old boy who died after suffering cardiac arrest while in foster care.

The St. Louis Post-Dispatch reports that the boy died Tuesday at a hospital.

The boy's name was not immediately released. St. Louis police spokeswoman Leah Freeman says the boy was a ward of the state, and authorities still are working to notify his relatives.

Police say emergency responders were summoned to a home about 3 p.m. Tuesday for a report of a toddler in cardiac arrest. The boy was pronounced dead at a hospital about seven hours later.

It is standard protocol to have child abuse detectives investigate sudden deaths involving children.

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