(AP) — Kansas City, Kan., police say an 11-month-old boy died after being found unresponsive at a day care center.

Firefighters were called to the Advantage Child Care Center Tuesday afternoon in Kansas City, Kan.

Day care workers said the toddler had been fussy and they thought he might be teething. They checked on him every 15 minutes while he was napping and eventually found him unresponsive.

Emergency responders took the boy to the University of Kansas Hospital, where he was pronounced dead.

An autopsy will be performed Wednesday to determine the cause of death.